Q: Car runs rough until warm, and then runs fine.

asked by on

The car runs roughly upon startup. Once the engine warms up, the car idles normally.

I would have a technician inspect your rough idle. He will probably also check for codes on the computer. It may be the air temperature sensor malfunctioning if it idles rough only when it’s cold. You may be able to remove it and clean it or replace it. If that doesn’t fix it, it may need to be checked out by a technician.

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. Car runs rough until warm, and then runs fine.

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: Engine leaks oil

Engine oil leaks are common and unavoidable as the vehicle ages. Most oil leaks are caused to engine seals and gaskets that have failed with age and stress. A qualified technician, such as one from YourMechanic, will be able to...

Q: Car vibrates in idle and trouble accelerating after stopped

Hi there, thanks for writing in about your 2003 Subaru Baja. There are dozens of potential causes for the symptoms you are having. It could be an engine performance problem, such as a bad sensor. It could also be a...

Q: 2007 Mercedes-Benz SL55 AMG on occasion will not shift up from first gear. What's the cause?

Hello there, many faults will cause your 2007 Mercedes SL55 to have issues upshifting from first gear. The most common faults are low transmission fluid level, shift solenoid, shift cable fault, transmission control module fault, or a failing valve body....

Related articles

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...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.