Skip the auto shop - Our mechanics make house calls

Q: Engine Computer Issues (spark plugs & coils were changed 5 months ago as well).

asked by on

About 6 months ago my eml/service & brake lights came on. The car started running rough & wouldn't go over 50mph. I had car towed to mechanic. After much investigation, the mechanic said the engine computer would need replaced. He didnt do this without much investigating. He is the local mechanic who does all imported cars in my city. He gets very high remarks from customers. He purchased a new computer from the BMW dealer. He did the programming and installed the unit. I got the car back and all was good. Last week, out of nowhere, when I started the car, the eml/service lights came on. The car was running rough again. This time the lights didn't always come on at startup. When not on, the car would run perfect. Car is back to mechanic. The codes he is getting are saying the eng. computer is a problem. He is still investigating because he doesn't understand how this happened. I am very confused too. Any ideas on what could be happening and what we should do? Help?

My car has 80000 miles.
My car has an automatic transmission.

A: Do you have ANY aftermarket electrical equi...

Do you have ANY aftermarket electrical equipment in the car? Such components can impact the function of the PCM. Also, check the alternator output and stability. If the power supply to the PCM is not within specification, that could damage or alter normal function of the PCM. Check for defective, inadequate, or missing ground wires and terminals as well.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: RPM fluctuation, engine shuts off at the traffic light

You may have a belt tensioner not suppling enough tension on the belt. The power steering may also be low on fluid. The belt may be loose which will need to be adjusted tighter. The idle problem may be due...

Q: Engine shuts down suddenly, battery red warning light on

I would say the tensioner was overlooked on the last repair and the oil pressure switch may have been damaged in the repair process. I would recommend having the repairs done, but ask for the old parts to see if...

Q: Electrical issues with my vehicle that is unexplained.

Hi there. It sounds like the door switches are not working and probably have a short in one or more switch. The back hatch door on the jeep will lock and unlock all of the doors. Its possible that the...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...