This is my daughters 1996 Lumina with the 3.1L engine. It starts fine, idles fine and drives fine, once you get it up to speed, but it doesn’t want to accelerate from a stop unless you kick the peddle all the way to the floor. I’ve changed fuel filter, plugs and wires, put in two new MAF sensors, a throttle position sensor and an air charge sensor. I’ve checked the fuel pressure and pressure regulator. I've run several cans of injector cleaner thru it. My OBDII scanner doesn't show any codes or any pending codes. I’ve taken it in to a garage, they thought it was the fuel pump, it wasn’t. They then told me it was a bad MAF sensor, so I replaced the aftermarket MAF that I put in with a new Delphi. That didn’t fix it either. Both of the MAF sensors did seem to make some improvement at first but then it gets progressively worse. One thing I have noticed is, if you run it without an air filter, it runs much better. I’ve changed air filter three times and tried two different brands. Always use paper filters, not the washable ones you have to oil – I know they’re bad for the MAF sensors. I don’t know what else to look for. Please point me in the right direction.
Oct 22, 2009 at 4:46 PM