P128A Code – Intermittent / Erratic Cylinder Head Temperature Sensor Circuit

P128A code possible causes

  • Faulty thermostat
  • Not within operating range
  • Engine overheated
  • Low coolant level
  • Faulty cylinder head temperature (CHT) sensor
  • Cylinder head temperature (CHT) sensor harness is open or shorted
  • Poor electrical connection in cylinder head temperature (CHT) sensor circuit

| How is P128A code repair performed?

Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

| What are the possible symptoms of P128A code?

  • Check Engine Light On (or Service Engine Soon Warning Light)

| What does P128A code mean?

The cylinder head temperature (CHT) sensor is mounted in the cylinder head wall and is not connected to any coolant passages. The CHT sends a signal to the Powertrain Control Module (PCM) indicating the cylinder head temperature. If the temperature exceeds 126°C (258°F), the PCM shuts off four fuel injectors at a time. The PCM will alternate the four disabled injectors every 32 engine cycles. The four cylinders that are not being injected with fuel act as air pumps to help cool the engine. If the temperature exceeds 154°C (310°F), the PCM shuts off all fuel injectors until the engine temperature drops below 154°C (310°F).

BMW Code P128A – Nitrogen Oxide Sensor Regeneration Nitrogen Oxide Catalyst Regeneration Monitoring

P128A BMW code possible causes

  • Faulty nitrogen oxide (NOx) sensor
  • Nitrogen oxide (NOx) sensor harness is open or short-circuited
  • Poor electrical connection in the nitrogen oxide (NOx) sensor circuit

| How is BMW P128A code repair performed?

Start by checking the “Possible Causes” listed above. Visually inspect the wiring harness and associated connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

| What are the possible symptoms of BMW P128A code?

  • Check Engine Light on (or Service Engine Soon warning light)

| What does BMW P128A code mean?

The Engine Control Module (ECM) monitors the nitrogen oxide (NOx) sensor. The ECM sets the OBDII code when the nitrogen oxide (NOx) sensor does not meet factory specifications.

P128A Code BUICK – Fuel Rail Pressure Sensor 1 Internal Performance

P128A Code BUICK Possible Causes

  • Faulty Fuel Rail Pressure Sensor 1
  • Fuel Rail Pressure Sensor 1 Harness is Open or Shorted
  • Fuel Rail Pressure Sensor 1 Circuit Poor Electrical Connection

| How is the P128A BUICK Code Repair Done?

Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

| What are the Possible Symptoms of P128A BUICK Code?

  • Engine Light On (or Service Engine Soon Warning Light)

| What Does P128A BUICK Code Mean?

The Fuel Rail Pressure Sensor transmits fuel pressure and temperature information via serial data. The internal microprocessor of the Fuel Rail Pressure Sensor allows 4 separate sensor outputs from a 3-wire sensor. The Engine Control Module (ECM) supplies the Fuel Rail Pressure Sensor with a 5V reference circuit, a low reference circuit, and an asynchronous/serial data signal circuit. The asynchronous signal means communication only goes from the Fuel Rail Pressure Sensor to the ECM. The ECM decodes the serial data signal into separate voltages that are displayed on a scan tool as Fuel Temperature Sensor, Fuel Rail Pressure Sensor, and Fuel Rail Pressure Sensor 2 voltage inputs.

Fuel Rail Pressure Sensor 1 Internal Performance

P128A Code CHEVROLET Possible Causes

  • Faulty fuel rail pressure sensor 1
  • Fuel rail pressure sensor 1 harness is open or shorted
  • Poor electrical connection in fuel rail pressure sensor 1 circuit

| How is the P128A CHEVROLET code repair performed?

Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

| What are the possible symptoms of P128A CHEVROLET code?

  • Engine light on (or Service Engine Soon warning light)

| What does P128A CHEVROLET code mean?

The fuel rail pressure sensor transmits fuel pressure and temperature information via serial data. The internal microprocessor of the fuel rail pressure sensor allows 4 separate sensor outputs from a 3-wire sensor. The Engine Control Module (ECM) supplies the fuel rail pressure sensor with a 5V reference circuit, a low reference circuit, and an asynchronous/serial data signal circuit. The asynchronous signal means communication only goes from the fuel rail pressure sensor to the ECM. The ECM decodes the serial data signal into separate voltages that are displayed on a scan tool as fuel temperature sensor, fuel rail pressure sensor, and fuel rail pressure sensor 2 voltage inputs.

P128A FORD Code – Intermittent/Erratic Cylinder Head Temperature Sensor Circuit

P128A Code FORD Possible Causes

  • Faulty thermostat
  • Not within operating range
  • Engine overheated
  • Low coolant level
  • Faulty Cylinder Head Temperature (CHT) sensor
  • Cylinder Head Temperature (CHT) sensor harness is open or shorted
  • Poor electrical connection in the Cylinder Head Temperature (CHT) sensor circuit

| How is the P128A FORD code repair performed?

Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

| What are the possible symptoms of the P128A FORD code?

  • Check Engine Light on (or Service Engine Soon warning light)

| What does the P128A FORD code mean?

The Cylinder Head Temperature (CHT) sensor is mounted in the cylinder head wall and is not connected to any coolant passages. The CHT sends a signal to the Powertrain Control Module (PCM) indicating the cylinder head temperature. If the temperature exceeds 126°C (258°F), the PCM shuts off four fuel injectors at a time. The PCM will alternate the four disabled injectors every 32 engine cycles. The four cylinders that are not injected with fuel act as air pumps to help cool the engine. If the temperature exceeds 154°C (310°F), the PCM shuts off all fuel injectors until the engine temperature drops below 154°C (310°F).

P128A Code LINCOLN – Intermittent/Irregular Cylinder Head Temperature Sensor Circuit

P128A code LINCOLN possible causes

  • Faulty thermostat
  • Not within operating range
  • Engine overheated
  • Low coolant level
  • Faulty Cylinder Head Temperature (CHT) sensor
  • Cylinder Head Temperature (CHT) sensor harness is open or shorted
  • Poor electrical connection in Cylinder Head Temperature (CHT) sensor circuit

| How is P128A LINCOLN code repair performed?

Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

, the vehicle’s make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.

| What are the possible symptoms of P128A LINCOLN code?

  • Check Engine Light on (or Service Engine Soon warning light)

| What does P128A LINCOLN code mean?

The Cylinder Head Temperature (CHT) sensor is mounted in the cylinder head wall and is not connected to any coolant passages. The CHT sends a signal to the Powertrain Control Module (PCM) indicating the cylinder head temperature. If the temperature exceeds 126°C (258°F), the PCM shuts off four fuel injectors at a time. The PCM will alternate the four disabled injectors every 32 engine cycles. The four cylinders that are not injected with fuel act as air pumps to help cool the engine. If the temperature exceeds 154°C (310°F), the PCM shuts off all fuel injectors until the engine temperature drops below 154°C (310°F).

Code P128A MERCURY – Intermittent/Irregular Cylinder Head Temperature Sensor Circuit

P128A Code MERCURY Cylinder Head Temperature

  • Not within operating range
  • Engine overheated
  • Low coolant level
  • Faulty Cylinder Head Temperature (CHT) sensor
  • Cylinder Head Temperature (CHT) sensor harness is open or shorted
  • Cylinder Head Temperature (CHT) sensor circuit poor electrical connection

| How is the MERCURY P128A Code Repair Done?

Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

| What are the Possible Symptoms of MERCURY P128A Code?

  • Engine Light On (or Service Engine Soon Warning Light)

| What Does MERCURY P128A Code Mean?

The Cylinder Head Temperature (CHT) sensor is mounted in the cylinder head wall and is not connected to any coolant passages. The CHT sends a signal to the Powertrain Control Module (PCM) indicating the cylinder head temperature. If the temperature exceeds 126°C (258°F), the PCM shuts off four fuel injectors at a time. The PCM will alternate the four disabled injectors every 32 engine cycles. The four cylinders that are not injected with fuel act as air pumps to help cool the engine. If the temperature exceeds 154°C (310°F), the PCM shuts off all fuel injectors until the engine temperature drops below 154°C (310°F).

Code P128B – Internal Performance of Fuel Rail Pressure Sensor 2

Possible causes of Code P128B

  • Faulty fuel rail pressure sensor 2
  • Fuel rail pressure sensor 2 harness is open or shorted
  • Poor electrical connection in the fuel rail pressure sensor 2 circuit

| How is Code P128B repaired?

Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

| What are the possible symptoms of Code P128B?

  • Engine light on (or Service Engine Soon warning light)

| What does Code P128B mean?

The fuel rail pressure sensor transmits fuel pressure and temperature information via serial data. The internal microprocessor of the fuel rail pressure sensor allows 4 separate sensor outputs from a 3-wire sensor. The Engine Control Module (ECM) supplies the fuel rail pressure sensor with a 5V reference circuit, a low reference circuit, and an asynchronous/serial data signal circuit. The asynchronous signal means communication only goes from the fuel rail pressure sensor to the ECM. The ECM decodes the serial data signal into separate voltages that are displayed on a scan tool as fuel temperature sensor, fuel rail pressure sensor, and fuel rail pressure sensor 2 voltage inputs.

BMW Code P128B – Nitrogen Oxide Sensor Regeneration

BMW P128B code possible causes

  • Faulty nitrogen oxide (NOx) sensor
  • Nitrogen oxide (NOx) sensor harness is open or short-circuited
  • Poor electrical connection in the nitrogen oxide (NOx) sensor circuit

| How is BMW P128B code repair performed?

Start by checking the “Possible Causes” listed above. Visually inspect the wiring harness and associated connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

| What are the possible symptoms of BMW P128B code?

  • Check engine light on (or Service Engine Soon warning light)

| What does BMW P128B code mean?

The engine control module (ECM) monitors the nitrogen oxide (NOx) sensor. The ECM sets the OBDII code when the nitrogen oxide (NOx) sensor does not meet factory specifications.

CHEVROLET Code P128B – Internal Performance of Fuel Rail Pressure Sensor 2

Possible causes of CHEVROLET code P128B

  • Faulty fuel rail pressure sensor 2
  • Fuel rail pressure sensor 2 harness is open or shorted
  • Poor electrical connection in fuel rail pressure sensor 2 circuit

| How is CHEVROLET code P128B repaired?

Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

| What are the possible symptoms of CHEVROLET code P128B?

  • Engine light on (or Service Engine Soon warning light)

| What does CHEVROLET code P128B mean?

The fuel supply rail pressure sensor transmits fuel pressure and temperature information via serial data. The internal microprocessor of the fuel supply rail pressure sensor enables 4 separate sensor outputs from a 3-wire sensor. The Engine Control Module (ECM) supplies the fuel supply rail pressure sensor with a 5V reference circuit, a low reference circuit, and an asynchronous/serial data signal circuit. Asynchronous signal means communication only goes from the fuel supply rail pressure sensor to the ECM. The ECM decodes the serial data signal into separate voltages that are displayed on a scan tool as fuel temperature sensor, fuel rail pressure sensor, and fuel rail pressure sensor 2 voltage inputs.