Engine Performance problem
2000 Chevy Impala 6 cyl Front Wheel Drive Automatic 166000 miles
My wifes 2000 Impala has begun to surge while driving with a constant throtle. If it begins to pull a little hill, it will surge from about 1700 rpm to 22 or 2300. I have replaced the fuel filter, fuel pump, fuel pressure regulator, plugs, and wires and have not found the source. The car is also not tripping any codes! I am completely at a loss now. Please help!
Check these: - Try cleaning your IAC valve. Some surge problems are related to a dirty or faulty IAC valve (or holes in IAC bypass hose).
- You may have a weak ignition system; what does the spark look like: yellow or blue? If yellow you have weak ignition coil. Also, make sure the spark is constant. If not you have a problem in your ignition system.
- You could also have a vacuum leak (check your vacuum lines, IAC bypass hose etc.).
- you said you replaced several parts on your fuel system, but have you checked the pressure?
- Make sure your catalytic converter is not plugged or broken.
August, 27, 2008 AT 6:50 PM
He is right. Check the fuel pressure. You may also wanna check the fuel injectors and see if they are plugging up. They may need to be cleaned. Fuel injector balance test can show you that. Also the cat converter is a very common thing to go bad in the impala