- Your “check engine” light is on.
- Other warning lights may be on, including traction control and ABS.
- You lose fuel economy for no apparent reason.
- Your car stutters when starting, requires multiple attempts, or won't start at all.
- Stuttering or stalling during idling.
What does a Ford PCM control?
The PCM controls ignition timing, fuel delivery, valve timing in engines with Variable Valve Timing), emissions functions, turbo boost pressure in turbocharged engines, idle speed, throttle position and cruise control.Mar 3, 2016
What is a failed PCM?
PCMs typically fail for one of two reasons: voltage overloads (often due to a short in a solenoid or actuator circuit) or environmental factors (corrosion, thermal stress or vibration). If the shorted solenoid or actuator isn't found and repaired, the voltage overload it creates may damage the replacement PCM, too.
What are the signs of a bad PCM?
- Your 'Check Engine' Light is On. ...
- Your Car Won't Start or Starts Roughly. ...
- Sudden Loss of Gas Mileage. ...
- You Failed Your Emissions Test. ...
- Your Engine Stutters or Stalls. ...
- Erratic or Random Shifting. ...
- You're Receiving a PCM-Related Error Code. ...
- What to Do If You Experience PCM Failure Symptoms.
What happens when the PCM fails?
A failed PCM or TCM can cause the car to get stuck in gear, which can be a serious safety issue. It can also lead to costly transmission damage.Aug 23, 2019
How do you troubleshoot a PCM?
- Locate your vehicle's PCM. ...
- Look specifically at the wiring harness. ...
- Locate your vehicle's diagnostic data port. ...
- Connect your OBD-II scanner to the diagnostic data port.
- Push your key into the vehicle's ignition cylinder. ...
- Watch the OBD-II device's read-out screen for the codes.
What will a bad PCM cause?
Bad PCM Causes Engine performance issues. Engine misfiring or stalling and overall poor engine performance are common indications of problems with the engine control unit. ... If you notice problems with performance, bad engine computers may be the issue.Feb 4, 2020
Will a car run with a bad PCM?
It is highly possible that symptoms of a bad PCM include the vehicle not running at all. All these components play a part in kicking off and running the engine. When they can't function properly, the car may not run at all. In that case, the engine will not crank or even if it does, it will not start.Feb 8, 2021
What happens if you have a bad powertrain control module?
A failed PCM or TCM can cause the car to get stuck in gear, which can be a serious safety issue. It can also lead to costly transmission damage.Aug 23, 2019