How severe is this DTC?

Any stored diesel particulate filter code can be a precursor to a clogged exhaust system. The stored code P200C should be considered severe and addressed as quickly as possible. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some of the symptoms of the code?

Symptoms of a P200C fault code may include:

• Decreased engine performance
• Excessive black smoke from vehicle exhaust
• Reduced fuel efficiency
• Other emission-related codes

What are some common causes of the code?

Causes

of this code may include:

• Non-functioning SCR system
• Faulty SCR injector
• Incorrect or insufficient DEF fluid
• Faulty exhaust temperature sensor
• Incorrect SCR controller or programming error
• Pre-catalyst exhaust leaks
• Installation of aftermarket or high-performance exhaust parts

What are the P200C troubleshooting steps?

If SCR codes are also stored, these should be addressed before attempting to diagnose the stored P200C. Pre-catalyst exhaust leaks must be repaired before attempting diagnosis for this type of code.

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), an infrared thermometer with a laser pointer, and a source of vehicle-specific diagnostic information to diagnose a P200C code.

If you can find a technical service bulletin (TSB) that matches the vehicle’s year, make, and model; as well as engine size, stored code/s, and presented symptoms, it could provide useful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the SCR injection system, exhaust temperature sensors, NOx sensors, and oxygen sensor (O2) harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much more difficult to diagnose (for now), if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the infrared thermometer to gather actual temperatures before and after the diesel particulate filters. Observe the scanner data stream to compare your actual results with the information found on the scanner data display screen. Also compare exhaust temperature sensor data between engine banks. If exhaust temperature inconsistencies are detected, test the respective sensors using the DVOM. Sensors not meeting manufacturer specifications should be considered faulty.

If all sensors and circuits appear to be functioning as expected, suspect that the diesel particulate filter is defective or the SCR system is malfunctioning.

Ensure the DEF tank is filled with the appropriate fluid and that the SCR system is operating as expected…

Understanding the Mercury P1443 Diagnostic Trouble Code

The OBD2 code P1443 is a manufacturer-specific diagnostic trouble code that primarily affects Ford and Mercury vehicles. This code indicates a problem within the Evaporative Emission Control (EVAP) system, specifically related to the purge flow monitoring during non-purge conditions. When this code appears, your vehicle’s powertrain control module (PCM) has detected an unexpected flow in the EVAP purge system when it should be closed.

What Does P1443 Mean for Your Mercury Vehicle?

P1443 specifically points to “EVAP System Purge Flow During Non-Purge Condition” in Mercury vehicles. The EVAP system is designed to prevent fuel vapors from escaping into the atmosphere by capturing and storing them in a charcoal canister, then purging them into the engine for combustion during normal operation. When the system detects purge flow occurring when the purge valve should be closed, it triggers the P1443 code and illuminates the check engine light.

How the EVAP System Works in Mercury Vehicles

The EVAP system in your Mercury consists of several key components working together:

• Charcoal canister for vapor storage
• Purge control valve/solenoid
• Vent control valve
• Fuel tank pressure sensor
• Various hoses and connections
• Fuel cap with sealing mechanism

This system operates under precise computer control to manage fuel vapors while maintaining proper engine performance and emissions compliance.

Common Symptoms and Immediate Effects of P1443

When the P1443 code activates in your Mercury, you may notice several symptoms that indicate an issue with your EVAP system. Recognizing these signs early can prevent more serious problems and potential inspection failures.

Check Engine Light and Driveability Issues

The most immediate symptom of P1443 is the illumination of the check engine light on your dashboard. While the vehicle may still be drivable, you might experience:

• Rough idling or unstable engine operation
• Reduced fuel efficiency
• Possible hesitation during acceleration
• Failed emissions testing in regions requiring compliance
• Fuel odor around the vehicle in severe cases

Long-Term Consequences of Ignoring P1443

While P1443 may not immediately disable your vehicle, ignoring it can lead to:

• Increased hydrocarbon emissions contributing to environmental pollution
• Potential damage to other EVAP system components
• Reduced engine performance over time
• Fuel economy degradation up to 10-15%
• Possible failure of state emissions testing programs

Diagnosing the Root Causes of P1443 in Mercury Vehicles

Proper diagnosis is crucial for effectively addressing the P1443 code. Several components and conditions can trigger this diagnostic trouble code, requiring systematic troubleshooting.

Primary Mechanical and Electrical Causes

The most common root causes for P1443 include:

• Faulty Purge Control Valve/Solenoid: The most frequent culprit, where the valve fails in the open position or doesn’t seal properly
• Damaged Vacuum Hoses: Cracked, disconnected, or deteriorated EVAP system hoses allowing unintended airflow
• Electrical Issues: Problems with wiring, connectors, or power supply to the purge solenoid
• Charcoal Canister Problems: Contamination or damage to the vapor storage canister
• PCM Software Issues: Rare cases where updated calibration is required

Diagnostic Procedure and Testing Methods

Professional technicians follow a specific diagnostic routine for P1443:

• Visual inspection of all EVAP system components and connections
• Functional testing of the purge control valve using a scan tool
• Smoke machine testing to identify vacuum leaks in the system
• Electrical testing of purge solenoid circuit including resistance checks
• Vacuum testing of the purge valve and related components
• Scan tool monitoring of EVAP system parameters during operation

Step-by-Step Repair Guide for P1443 Code

Addressing P1443 requires methodical approach and proper tools. While some repairs can be DIY projects, others may require professional assistance.

Replacing the Purge Control Valve/Solenoid

The purge valve replacement is typically the first repair attempt for P1443:

• Locate the purge valve (usually near the engine bay or charcoal canister)
• Disconnect the electrical connector and vacuum hoses
• Remove the mounting hardware and old valve
• Install the new valve using reverse procedure
• Clear codes and test drive to verify repair
• Use OEM or high-quality replacement parts for reliability

Addressing Vacuum Leaks and Hose Issues

Vacuum leaks require thorough inspection and replacement of damaged components:

• Inspect all EVAP system hoses for cracks, brittleness, or disconnections
• Check hose routing against factory specifications
• Replace damaged hoses with EVAP-rated replacement parts
• Ensure all connections are secure and properly seated
• Perform smoke test to verify leak resolution

Preventive Maintenance and System Verification

After repairing P1443, proper verification and maintenance can prevent recurrence and ensure long-term system reliability.

Post-Repair Verification Procedures

Always verify your repair was successful:

• Clear all diagnostic trouble codes using your scan tool
• Perform a complete drive cycle to allow system monitors to run
• Verify all emission monitors complete successfully
• Check for any pending codes after multiple drive cycles
• Confirm normal engine operation and fuel economy restoration

Long-Term EVAP System Maintenance Tips

Prevent future EVAP system issues with these maintenance practices:

• Always tighten the fuel cap properly until it clicks
• Replace the fuel cap every 50,000 miles or if damaged
• Have EVAP system inspected during routine maintenance
• Avoid overfilling the fuel tank beyond the automatic shutoff
• Address check engine lights promptly to prevent additional damage
• Follow manufacturer-recommended service intervals for emission systems

The P1443 code in Mercury vehicles, while not an emergency, requires timely attention to maintain optimal vehicle performance, fuel efficiency, and emissions compliance. With proper diagnosis and repair, this issue can be resolved effectively, restoring your vehicle’s emission system to proper operation.

How Severe Is This DTC?

Any stored diesel particulate filter code can be a precursor to a clogged exhaust system. The stored code P200D should be considered severe and addressed as quickly as possible. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What Are Some of the Symptoms of the Code?

Symptoms of a P200D fault code may include:

• Decreased engine performance
• Excessive black smoke from the vehicle’s exhaust
• Reduced fuel efficiency
• Other emission-related codes

What Are Some Common Causes of the Code?

Causes of this code may include:

• Non-operational SCR system
• Faulty SCR injector
• Incorrect or insufficient DEF fluid
• Faulty exhaust temperature sensor
• Incorrect SCR controller or programming error
• Pre-catalyst exhaust leaks
• Installation of aftermarket or high-performance exhaust parts

What Are the P200D Troubleshooting Steps?

If SCR codes are also stored, these should be addressed before attempting to diagnose the stored P200D. Pre-catalyst exhaust leaks must be repaired before attempting diagnosis for this type of code.

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), an infrared thermometer with a laser pointer, and a source of vehicle-specific diagnostic information to diagnose a P200D code.

If you can find a technical service bulletin (TSB) that matches the vehicle’s year, make, and model; as well as the engine size, stored code(s), and presented symptoms, it could provide helpful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the SCR injection system, exhaust temperature sensors, NOx sensors, and oxygen sensor (O2) harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much more difficult to diagnose (for the time being) if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the infrared thermometer to gather actual temperatures before and after the diesel particulate filters. Observe the scanner data stream to compare your actual results with the information found on the scanner’s data display screen. Also compare exhaust temperature sensor data between engine banks. If exhaust temperature inconsistencies are detected, test the respective sensors using the DVOM. Sensors not meeting manufacturer specifications should be considered faulty.

If all sensors and circuits appear to be functioning as expected, suspect that the diesel particulate filter is defective or the SCR system is malfunctioning.

Ensure the DEF tank is filled with the appropriate fluid and that the SCR system is operating as expected

Error Code P200E: Severity, Symptoms, and Solutions

Severity of Code P200E

The P200E code is a critical code that must be addressed promptly. It is related to the selective catalytic reduction (SCR) system and the catalyst.

➡ Main risk: A clogged or ineffective catalyst can lead to increased pollutant emissions and engine damage if the issue is not resolved quickly.

Possible Symptoms

• Decreased engine performance.
• Excessive black smoke from the exhaust.
• Higher fuel consumption.
• Presence of other emission-related error codes.

Common Causes

• SCR system failure.
• Faulty SCR injector.
• Insufficient DEF fluid level or poor-quality fluid.
• Faulty exhaust temperature sensor.
• SCR controller issue or programming error.
• Exhaust leaks before the catalyst.
• Installation of non-compliant or modified exhaust parts.

Diagnostic and Repair Steps

1. Checking Associated Error Codes

• If other SCR codes are present, diagnose them first before addressing P200E.
• Check if there is a Technical Service Bulletin (TSB) specific to your vehicle.

2. Visual Inspection

• Inspect the SCR system wiring, exhaust temperature sensors, and NOx sensors.
• Ensure there are no burnt wires, cut wires, or corroded connectors.

3. Checking Catalyst Temperatures

• Use an infrared thermometer to measure the temperature before and after the catalyst.
• Compare the data with that from the OBDII scanner.

4. Testing Sensors and the SCR System

• If temperature inconsistencies are detected, test the temperature sensors with a multimeter (DVOM).
• Ensure the DEF fluid is present and meets the manufacturer’s specifications.
• Check the operation of the SCR injector.

5. Checking the Catalyst

• If everything appears correct but the problem persists, the catalyst may be faulty and require replacement.

6. Clearing the Code and Road Testing

• Once repairs are completed, clear the code and test the vehicle until the PCM enters readiness mode or the code reappears.

If the problem persists, professional intervention may be necessary for a thorough diagnosis.

How severe is this DTC?

Any stored catalyst system code can be a precursor to a clogged exhaust system. The stored code P200F should be considered severe and addressed as soon as possible. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some of the symptoms of the code?

Symptoms of a P200F trouble code may include:

• Decreased engine performance
• Excessive black smoke from vehicle exhaust
• Reduced fuel efficiency
• Other emission-related codes

What are some common causes of the code?

Causes of this code may include:

• Non-functioning SCR system
• Faulty SCR injector
• Incorrect or insufficient DEF fluid
• Faulty exhaust temperature sensor
• Incorrect SCR controller or programming error
• Pre-catalyst exhaust leaks
• Installation of aftermarket or high-performance exhaust parts

What are the troubleshooting steps for P200F?

If SCR codes are also stored, these should be addressed before attempting to diagnose the stored P200F. Pre-catalyst exhaust leaks must be repaired before attempting diagnosis for this type of code.

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), an infrared thermometer with a laser pointer, and a source of vehicle-specific diagnostic information to diagnose a P200F code.

If you can find a technical service bulletin (TSB) that matches the vehicle’s year, make, and model; as well as engine size, stored code(s), and presented symptoms, it could provide helpful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the SCR injection system, exhaust temperature sensors, NOx sensors, and oxygen sensor (O2) harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much more difficult to diagnose (for now) if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the infrared thermometer to gather actual temperatures before and after the catalyst. Observe the scanner data stream to compare your actual results with the information found on the scanner’s data display screen. Also compare exhaust temperature sensor data between engine banks. If exhaust temperature inconsistencies are detected, test the respective sensors using the DVOM. Sensors not meeting manufacturer specifications should be considered faulty.

If all sensors and circuits appear to be functioning as expected, suspect that the catalyst element is defective or the SCR system is malfunctioning.

Ensure the DEF tank is filled with the appropriate fluid and that the SCR system is operating as expected

Symptoms

Symptoms of a P2010 code may include:

• Hesitation during acceleration
• Reduced engine performance, especially at low RPM
• Rich or lean exhaust
• Reduced fuel efficiency
• Engine surging

Causes

Possible causes of this engine code include:

• Loose or binding intake manifold runner controls
• Faulty IMRC actuator solenoid
• Bad intake manifold runner control position sensor
• Open or shorted wiring in the IMRC actuator solenoid control circuit
• Carbon buildup on IMRC flaps or intake manifold ports
• Faulty MAP sensor
• Corroded IMRC actuator solenoid connector face

Diagnostic and Repair Procedures

A diagnostic scanner, digital volt/ohmmeter (DVOM), and reliable vehicle information source will be needed to diagnose a P2010 code. I find it helpful to check Technical Service Bulletins (TSBs) for the specific symptoms, stored codes, and make and model of the vehicle in question before starting any diagnosis. If you find a TSB related to the code/symptoms in question, the information it contains will likely help diagnose the code as TSBs are packed with thousands of repairs.

A convenient starting point for any diagnosis is a visual inspection of the system wiring and connector faces. Knowing that IMRC actuator connectors are prone to corrosion and this could cause an open circuit, one might focus attention on inspecting these areas.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and freeze frame data. Note this information, just in case it’s an intermittent code. Then clear the codes and test drive the vehicle to see if the code resets.

Next, access the IMRC actuator solenoid and IMRC runner position sensor if the code resets. Consult your vehicle information source for specifications, then use the DVOM to perform resistance tests on the solenoid and sensor. Replace either component if it doesn’t meet specifications and retest the system.

To avoid damaging the PCM, disconnect all associated controllers before testing circuit resistance with the DVOM. If the actuator and sensor resistance levels meet manufacturer specifications, use the DVOM to test resistance and continuity on all system circuits.

Additional Diagnostic Notes:

Carbon coking inside intake manifold walls can cause IMRC flaps to bind
Be careful when handling small screws or rivets in or near intake manifold openings
Test IMRC flap binding with the actuator disconnected from the shaft
The screws (or rivets) that secure the flaps to the shaft may loosen or fall out, causing the flaps to jam

Symptoms

Symptoms of a DTC P2011 may include:

1. The engine may have a rougher idle than normal
2. Sometimes, the engine may tend to surge
3. There may be a slight reduction in low-end torque
4. The fault code P2011 will be displayed
5. This is a “software” code, meaning the check engine light may only flash when the ECM detects the fault. If the fault corrects itself, the light turns off. Hard codes will remain once observed until they are cleared.

Potential Causes

Causes

of this DTC may include:

Over the years, I have found that the intake manifold runner control solenoid is largely the issue. They are almost always located where they are exposed to heat and dirt that clogs the filter and causes them to fail. Secondly, the swirl flaps themselves become coated with soot from the EGR valve and lock in their current position.
The MAF sensor or the EGR have the potential to set this code if they fail, however, they will set their own code to coincide with the P2011 code. In that case, they would be diagnosed and repaired first and the codes cleared

• The intake manifold runner control solenoid
• The swirl flaps are contaminated
• Cracked vacuum lines
• Poor electrical connection
• Open or short circuit in the wiring harness

Diagnosis and Repair

A vehicle service manual and a scan tool will be needed to diagnose and perform a conclusive repair. The ECM uses pulse width modulation to vary the position of the swirl flaps with the intake runner solenoid.

• Check the vacuum hoses and ensure there are no cracks and that they are properly seated.
• Inspect the electrical connector of the solenoid. Look for corrosion or a loose connection.
• Disconnect the solenoid connector and plug the scan tool into the solenoid connector.
• Access the VSV operational check. Turn the key. Operate the solenoid with the scanner by making it open and close. If it does not respond, replace the valve.
• If the valve operates but struggles to move the actuator rod, replace the intake manifold.
• If the solenoid does not operate, disconnect the electrical connector. Look in the main fuse box and pull the EFI relay. Using an ohmmeter, check for continuity between the EFI terminals and the solenoid terminals on the harness side.
• Consult the service manual and locate the ground terminal on the solenoid harness connector and test it for ground.

Understanding the Mercedes-Benz P1443 Diagnostic Trouble Code

The P1443 diagnostic trouble code is a manufacturer-specific code that appears exclusively in Mercedes-Benz vehicles. This code indicates a malfunction within the Evaporative Emission Control (EVAP) system, specifically related to the Leak Detection Pump (LDP) circuit. The EVAP system is crucial for preventing fuel vapors from escaping into the atmosphere, and the Leak Detection Pump serves as the system’s primary diagnostic component. When the vehicle’s Engine Control Module (ECM) detects an irregularity in the LDP’s operation or electrical circuit, it stores the P1443 code and illuminates the check engine light.

What is the EVAP System and Why It Matters

The Evaporative Emission Control system is an essential environmental component in modern vehicles. Its primary function is to capture and store fuel vapors from the fuel tank, preventing them from escaping into the atmosphere. The system consists of several key components:

• Charcoal canister for vapor storage
• Purge valve for vapor management
• Fuel tank pressure sensor
• Leak Detection Pump (LDP)
• Various hoses and vent lines

Mercedes-Benz vehicles utilize a sophisticated leak detection system that actively tests the EVAP system’s integrity during specific driving conditions.

The Role of the Leak Detection Pump in Mercedes Vehicles

The Leak Detection Pump in Mercedes-Benz vehicles serves a dual purpose. It functions as both a vacuum source and a diagnostic tool for the EVAP system. During normal operation, the LDP creates a small vacuum within the EVAP system, allowing the ECM to monitor pressure changes and detect potential leaks. The pump operates through a combination of electrical signals and mechanical action, making it susceptible to various failure modes that can trigger the P1443 code.

Common Symptoms of P1443 Code in Mercedes-Benz

When the P1443 code appears in your Mercedes-Benz, you may notice several distinct symptoms that indicate EVAP system issues. While some symptoms are immediately noticeable, others might only be detectable through specialized diagnostic equipment.

Immediate Warning Signs and Driver Notifications

The most common and immediate indication of a P1443 code is the illumination of the check engine light on your dashboard. Depending on your specific Mercedes model and the severity of the issue, you might also experience:

• Illuminated check engine light (MIL)
• Possible failed emissions test
• Fuel odor around the vehicle
• Decreased fuel efficiency in some cases
• Rough idle or occasional engine performance issues

Secondary Effects on Vehicle Performance

While the P1443 code primarily affects the emissions system, prolonged issues can lead to secondary performance concerns. The vehicle’s ECM may enter a limited performance mode, and the continuous operation of faulty components can strain other electrical systems. However, it’s important to note that this code typically doesn’t cause immediate drivability problems or safety concerns.

Primary Causes of P1443 Code in Mercedes Models

Diagnosing the root cause of a P1443 code requires understanding the various components that can fail within the EVAP leak detection system. The issue can range from simple electrical problems to complex mechanical failures.

Electrical and Circuit-Related Causes

Electrical issues represent a significant portion of P1443 diagnoses. Common electrical problems include:

• Faulty Leak Detection Pump electrical connector
• Damaged wiring harness to the LDP
• Corroded electrical terminals
• Blown fuses affecting the EVAP system
• Poor ground connections
• ECM communication errors

Mechanical and Component Failures

Mechanical failures within the Leak Detection Pump and related components are equally common. These include:

• Failed Leak Detection Pump motor or mechanism
• Cracked or damaged LDP housing
• Clogged vacuum lines or filters
• Faulty EVAP system valves
• Damaged charcoal canister
• Compromised O-rings or seals

Professional Diagnostic Procedure for P1443

Proper diagnosis of the P1443 code requires a systematic approach using appropriate diagnostic tools and following manufacturer-recommended procedures. Attempting repairs without proper diagnosis can lead to unnecessary part replacement and continued issues.

Initial Diagnostic Steps and Safety Precautions

Begin the diagnostic process with these essential steps:

• Verify the code with an OBD2 scanner and check for additional codes
• Perform a visual inspection of all EVAP system components
• Check for technical service bulletins (TSBs) for your specific Mercedes model
• Inspect all electrical connections for corrosion or damage
• Verify proper battery voltage and charging system operation

Advanced Testing Procedures

For accurate diagnosis, follow these advanced testing procedures:

• Perform LDP activation tests using a professional scan tool
• Check LDP electrical resistance and compare to specifications
• Test circuit continuity between LDP and ECM
• Perform smoke testing to identify vacuum leaks
• Monitor real-time EVAP system parameters during operation
• Verify proper vacuum generation from the LDP

Repair Solutions and Cost Considerations

Once the root cause of the P1443 code has been identified, appropriate repairs can be undertaken. The complexity and cost of repairs vary significantly depending on the specific issue and your Mercedes model.

Common Repair Procedures

Typical repairs for P1443 code resolution include:

• Leak Detection Pump replacement
• EVAP line repair or replacement
• Electrical connector repair
• Wiring harness repair
• Charcoal canister replacement
• ECM software updates or replacement

Cost Analysis and Parts Information

Repair costs for P1443 code resolution can range from $200 to $800 or more, depending on the required parts and labor. The Leak Detection Pump itself typically costs between $150 and $400 for genuine Mercedes parts. Labor time varies from 1 to 3 hours, depending on the vehicle model and accessibility of components. Always use quality replacement parts and consider professional installation for complex electrical components.

Prevention and Maintenance Tips

Preventing P1443 code recurrence involves regular maintenance and awareness of potential issues. Following these guidelines can help maintain your Mercedes EVAP system’s integrity.

Regular Maintenance Practices

Implement these maintenance practices to prevent EVAP system issues:

• Follow manufacturer-recommended service intervals
• Address check engine lights promptly
• Keep the fuel cap properly sealed and replace when worn
• Regularly inspect visible EVAP components during service
• Use quality fuel from reputable stations

Long-term EVAP System Care

For long-term EVAP system health, consider these additional practices:

• Avoid overfilling the fuel tank
• Address any fuel odors immediately
• Have the system professionally inspected during routine maintenance
• Keep the engine compartment clean to prevent electrical corrosion
• Use dielectric grease on electrical connections during repairs

Proper diagnosis and repair of the P1443 code require technical knowledge and appropriate tools. While some basic inspections can be performed by knowledgeable owners, complex diagnostics and repairs should be handled by qualified automotive professionals familiar with Mercedes-Benz systems. Addressing the P1443 code promptly not only ensures your vehicle remains emissions-compliant but also helps maintain optimal performance and efficiency.

Symptoms

Symptoms of a P2012 code may include:

• Hesitation during acceleration
• Reduced engine performance, especially at low RPM
• Rich or lean exhaust
• Decreased fuel efficiency
• Engine surging

Causes

Possible causes of this engine code include:

• Loose or binding intake manifold runners, bank 2
• Faulty IMRC actuator solenoid, bank 2
• Faulty intake manifold runner position sensor, bank 2
• Open or shorted wiring in the IMRC actuator solenoid control circuit
• Carbon buildup on IMRC flaps or intake manifold ports
• Faulty MAP sensor
• Corroded IMRC actuator solenoid connector face

Diagnostic and Repair Procedures

When attempting to diagnose a P2012 code, a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable vehicle information source will be essential. It is wise to check Technical Service Bulletins (TSBs) for specific symptoms, stored codes, and the vehicle’s make and model before any diagnosis. If you find a related TSB, the information will often help diagnose the code in question, as TSBs are packed with thousands of repairs.

A fantastic starting point for any diagnosis is a visual inspection of the system’s wiring and connector faces. Knowing that IMRC actuator connectors are prone to corrosion, which could cause an open circuit, one might focus attention on this area.

You can proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and freeze frame data. Writing down this information, in case it’s an intermittent code, is a good practice. Now, clear the codes and test-drive the vehicle to see if the code resets.

Continuing, if the code resets, access the IMRC actuator solenoid and IMRC runner position sensor. Consult your vehicle information source for testing specifications and use the DVOM to perform resistance tests on the solenoid and sensor. If any of these components do not meet specifications, replace them and retest the system.

To prevent damage to the PCM, disconnect all associated controllers before testing circuit resistance with the DVOM. Use the DVOM to test resistance and continuity on all system circuits if the actuator and sensor resistance levels meet manufacturer specifications. Short or open circuits will need to be repaired or replaced as necessary.

Additional Diagnostic Notes:

• Carbon coking inside the intake manifold walls can cause IMRC flaps to bind
• Be cautious when handling small screws or rivets in or near intake manifold openings
• Test IMRC flap binding with the actuator disconnected from the shaft
• Screws (or rivets) that secure the flaps to the shaft may loosen or fall out, causing the flaps to jam

Symptoms

Symptoms of a P2013 code may include:

• Hesitation during acceleration
• Reduced engine performance, especially at low RPM
• Rich or lean exhaust
• Decreased fuel efficiency
• Engine surging

Causes

Possible causes of this engine code include:

• Loose or binding intake manifold runner controls, bank 2
• Faulty IMRC actuator solenoid, bank 2
• Defective intake manifold runner position sensor, bank 2
• Open or shorted wiring in the IMRC actuator solenoid control circuit
• Carbon buildup on IMRC flaps or intake manifold ports, bank 2
• Faulty MAP sensor
• Corroded IMRC actuator solenoid connector face

Diagnostic and Repair Procedures

Diagnosing a P2013 code requires a diagnostic scanner, digital volt/ohmmeter (DVOM), and reliable vehicle information source. Checking Technical Service Bulletins (TSBs) for specific symptoms, stored codes, and the vehicle’s make/model before starting diagnostics is helpful. If a relevant TSB is found, its information will likely aid diagnosis since TSBs document numerous repairs.

A practical diagnostic starting point is visual inspection of system wiring and connector faces. Given IMRC actuator connectors’ corrosion susceptibility (which could cause open circuits), focus attention on these areas.

Connect the scanner to the vehicle’s diagnostic port to retrieve stored codes and freeze frame data. Record this information in case of intermittent codes. Then clear codes and test-drive to see if the code returns.

If the code recurs, access the IMRC actuator solenoid and IMRC runner position sensor. Consult vehicle information sources for specifications, then use the DVOM to perform resistance tests on both components. Replace any non-compliant parts and retest the system.

To prevent PCM damage, disconnect all associated controllers before circuit resistance testing with the DVOM. If actuator and sensor resistance meet manufacturer specifications, use the DVOM to test resistance and continuity across all system circuits.

Additional Diagnostic Notes:

• Carbon coking inside intake manifold walls can cause IMRC flap binding
• Exercise caution when handling small screws or rivets near intake manifold openings
• Test IMRC flap binding with actuator disconnected from shaft
• Screws (or rivets) securing flaps to the shaft may loosen or fall out, causing flap blockage…