Skip the auto shop - Our mechanics make house calls

Q: Sometimes my car has a rough idle and even stalls - 2004 Chevrolet Tahoe

asked by on

I've been having a rough idle and sometimes even stalling. RPMs drop, volts drop, and oil pressure gauge drops. No problems going down the road. Also if I pour a can of seafoam in the tank at every fill up in won't have any issues. Things that I've done already: 1. Had throttle body and injectors cleaned 3k miles ago 2. Changed to synthetic oil 3. Cleaned mass air flow sensor 4. New air filter 5. New battery 6. Alternator is less than a year I have owned this Tahoe for almost 5 months. When I had the throttle body cleaned the shop said it looked like it had never been cleaned. Running seafoam in the tank will have it running smoothly, but as soon as I do not add it the problem comes right back. Not sure if the throttle body and injectors need to be cleaned again or if it's something else.

My car has 124000 miles.
My car has an automatic transmission.

A: Hello. From my experience with this engine,...

Hello. From my experience with this engine, the issue is usually due to the fact that the throttle body plate is worn out in the bore, or, more commonly, it is caused by an issue with the intake manifold gasket leaking. I always scan for codes first and check the fuel trim readings which would tell me if this is an air leak issue. Then I check for leaks around the intake gasket. It can also be a failure in the MAF, but that is not as common.

If you want to have this low idle fixed, consider having a certified mechanic, such as one from YourMechanic, come to your home or office to diagnose why the car is idling rough.

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

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!

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: Car wobbles in the rear.

You could have a bent rim or a bent hub. I would have the rim and hub checked to see which one is bent. I would recommend having a mechanic, like the certified ones at YourMechanic, come and check it...

Q: Need to know if my alternator is bad.

Hey there, thank you for asking about your 2005 Chevrolet Silverado 1500. Disconnecting the battery while the vehicle is running can damage the Powertrain Control Module (aka, vehicle "brain" or "engine computer") or other electrical components due to voltage excursions...

Q: Low idle on van

A low idle can be caused by many things for example a bad Idle Air Control Valve, or faulty catalytic converter. There are so many variables that it is best to seek the help of a technician for a good...

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...
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...
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...