Q: Car idling rough after replacing alternator

asked by on

My car is idling very rough after replacing alternator

My car has 161000 miles.
My car has an automatic transmission.

After replacing the alternator, your vehicle’s ECM will need to go through a "relearning" process whereby it will take a day or two for it to relearn the computer’s parameters and adjust. If by replacing the alternator, the battery was also presumably dead at some point, this will cause the ECM to need to relearn some of the fuel injection memory related to programming, fuel curves, etc. When this happens, you will notice a bit of rough idling and potentially, loss of power until the ECM relearns all of this information.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Car idling rough after replacing alternator

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: Bmw 745i Transmission Failsafe

Transmission Failsafe means that the transmission controller has detected a problem with the transmission or any of it's sensors that is preventing it from working properly. In your case it seems to see a problem when you attempt to get...

Q: Exhaust gases in coolant

Q: Car making a thumping sound/vibration as I'm driving

There are a number of things that may cause this kind of thumping sound that may be consistent with speeding up and slowing down, but it sounds like you may have a wheel bearing that might be failing. A wheel...

Related articles

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...
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...
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.