Skip the auto shop - Our mechanics make house calls

Q: My car has a rough idle and misfires once its warmed up

asked by on

Took screen out of mad sensor and problems started from there misses and cuts out once warmed up can be driving at 60mph and it surges and cuts out while driving then sitting at stop lights it's rough and exhaust is horrible and white smoke out of one pipe and the other blows black stuff out also changed plugs and wires checked then a week later and one side was fine the other was black

My car has 241000 miles.
My car has an automatic transmission.

A: Hi, and thanks for contacting YourMechanic....

Hi, and thanks for contacting YourMechanic. First of all, the mass air flow (MAF) sensor requires its screen; the air registering through the sensor is monitored with the elements in the screen. By removing the screen, you actually destroyed the sensor. I recommend replacing the MAF sensor before testing anything else on the vehicle. If you need assistance troubleshooting this issue, or the problems continue, then seek out a certified technician, such as one from YourMechanic, to assist you with your rough idle and engine misfires.

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: How to set a carburetor on a big block 454? I think the carburetor is a 600 cm

Hi - As excited as most of our team would be to work on a classic, big-block 'Vette, that is not a service we can offer at this time. I would check references by other Corvette forum members on a...

Q: Misfire on cylinder 8

Misfires are caused by lack of fuel or the ignition system isn't providing the needed spark. At least these are the most common single cylinder failures. It is possible, all be it remotely, that you have a compression problem, but...

Q: Starting problem, engine revs at low RPM in drive - 1999 Chevrolet C3500

It sounds like the Idle Air Control valve is gunked up. It may be possible to clean it, or it might have to be replaced. A YourMechanic professional can help to diagnose the stalling issue and replace the idle air...

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...
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...