Skip the auto shop - Our mechanics make house calls

Q: Idle rough when engine warm.

asked by on

Starts fine-once engine warms up car idles rough. Can not be driven until engine cools down.
My car has an automatic transmission.

A: There are a few possible problems that coul...

There are a few possible problems that could cause these symptoms. It could have a failed coolant temperature sensor, which reports the temperature of the engine to the engine control module. The engine control module uses this info to determine how much fuel to inject for the given engine temperature. It could also have a failed manifold absolute pressure (MAP) sensor, or a bad intake air temperature sensor. I suggest having the system diagnosed by a qualified professional, such as one from YourMechanic, who can quickly and accurately diagnose the rough running and provide you with a suggested repair.

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・Fair and transparent pricing

Get a quote

What others are asking

Q: Rattling noise coming from my car - 2006 Chevrolet Cobalt

Hi there. Rattling noises can be caused by very many things. The noise needs to be isolated to determine whether the noise is internal (inside the engine or transmission) or external (an accessory component, e.g., A/C compressor, water pump, alternator,...

Q: My car has no spark - 1992 Audi 100

First thing to check is what diagnostic codes the engine management system contains. Yes, even pre-OBD-II cars can have on-board diagnostics. In the fuse box, there are a pair of 2-pin connectors: one white and one black. With the ignition...

Q: Car won't start

Hi there! There first thing to check is your battery voltage. This can be done with a multi-meter. Simply place the red probe to the positive terminal and the black probe to the negative terminal, you should get at LEAST...

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...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.