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

asked by on October 27, 2016

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.

Car idle is rough Inspection $94.99 - $114.99 Get a Quote

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.

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Heater and fan not working
Hello. There are several things that could cause that heater to not work properly and the fan to only blow air on high. It is possible that you have a bad thermostat, which would cause the lack of heat. It...
Truck making loud gear noise when driving
This type of noise is typical of a bad hub bearing. When you turn left, you put more pressure on the right tire stressing the already bad bearing. This is why the noise seems to get louder. Bad hub bearings...
Code p0101
The P0101 trouble code (https://www.yourmechanic.com/article/-p0101-obd-ii-trouble-code-mass-airflow-maf-circuit-operating-range-or-performance-problem-by-john-nelson) may keep returning if the engine computer does not see the MAF sensor input within a specified range when it is testing the MAF input. The input can be wrong if the engine has another...
Car self-accelerates intermittently
Hello. The odor of oil is merely coincidental to the symptoms you report. Any vehicle of that vintage is going to have multiple oil leaks unless the engine has been re-sealed or re-built. Just be sure the leak is not...
Windshield wipers get stuck
Hi there. It sounds like there is a restriction in the linkage (https://www.yourmechanic.com/services/windshield-wiper-linkage-replacement) that your wiper motor (https://www.yourmechanic.com/services/windshield-wiper-motor-replacement) is connected to. It is possible that one of the rods has been bent and now does not move as it was...
I want to put an exhaust system on my car but it is not street legal, what can I do?
When it comes to this type of exhaust system, there is no workaround that will make it legal. If these exhaust components do not have the air quality resource tag on them, then they cannot legally be used on the...
Check engine light came on AutoZone said thermostat or gasket
To maximally help you, we need to know the specific diagnostic trouble code that was downloaded. The code will be a "format" such as P0135, just as one example. If you request a check engine light diagnostic (https://www.yourmechanic.com/services/check-engine-light-is-on-inspection) a certified...
Air noise when I turn steering wheel 2003 Chrysler Sebring
Hello - the "air noise" or hissing you hear when turning the steering wheel is probably due to a low fluid level in your power steering (https://www.yourmechanic.com/article/how-to-buy-good-quality-power-steering-fluid) system. If the fluid level gets low enough, power assist may be lost...
change exhaust gas recirculation sensor
Hi Damon. Thanks for contacting us today. I've forwarded your inquiry to our sales and service department to see if they can work up an estimate for these services. The problem is that several of these codes indicate a possible...

Related articles

Symptoms of a Bad or Failing Oxygen Sensor
Common signs of a faulty car oxygen sensor include the Check Engine Light coming on, bad gas mileage, and a rough idle.
How Long Does a Top Dead Center (TDC) Sensor Last?
The The top dead center (TDC) sensor is the point from which the firing order is determined and the ignition system measurements are taken. The measurements are normally defined as before top dead center and after top dead center. The...
How to Re-Start Your Second Generation Prius
Nobody Nobody wants their car to suddenly stop working. Unfortunately, Toyota recalled around 75,000 of their 2004 Prius cars because of some technical issues that were causing them to stall. This could be caused by several different failures in the...