Q: Engine noise, RPM fluctuation, ABS, 4x4 warning on

asked by on

Several days ago, the dash in my car started showing the check engine light on. The car went into a limp mode. After I restarted it, the car began to shake badly and the engine shut off. I attempted to start it back up but it shut off again. I took it to a mechanic and he opened the hood. The engine was making clicking sounds. I was told that the problem was the timing chain had been skipping. He had the valves and gaskets replaced and there were no engine noises afterwards. However, another problem appeared. The RPMs would jump up and down erratically. The fluctuation of RPMs was occuring at higher speeds as well as during idling.

One time, I was driving at 90 mph, and it just switched to neutral. At that point, the dash was showing the ABS light on, the check engine light on and the 4x4 error. After taking the car to the mechanic again, the error code appeared indicating the turbo cooler. After having the turbo radiator replaced, and the car was restarted, another error code popped up showing the throttle issue. However, the throttle body checks out fine. I was told that I would need a DME replacement due to bad ECU. As I have already spent a lot of money, I'm reluctant to pay even more for something that might not be the cause of the problem. What do you think? Should I get it replaced or is there something else causing this?

Hello. It sounds like you have a problem with the DME (digital motor electronics) and the ECU (engine control unit). It would not be a mistake to have these two things replaced. It is an expensive repair but I’m confident that this will solve your issue.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 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

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  1. Home
  2. Questions
  3. Engine noise, RPM fluctuation, ABS, 4x4 warning on

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Rattling and bumping noises underneath car & getting worse

Hello. Unfortunately, if this is not a mechanical repair to the powertrain it would not be considered under the Lemon Law. Most of the time this noise comes from the exhaust. In a lot of cases, unbolting the exhaust and...

Q: Car won't run over certain mileage

If there are any Check Engine lights or other dash lights on, the car might be stuck in limp home mode. This is a computer failsafe mode that disables certain features for passenger safety because it has detected a major...

Q: Engine won't crank and seems like it is frozen.

If the engine is seized, it certainly will not crank. This can be checked by attaching a breaker bar to the crank pulley bolt and trying to turn the engine over by hand. A qualified technician from YourMechanic can perform...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
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 Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...