Questions and Answers

Grand Prix P0300 Q. Vincent, My name is Dan and I have a 1997 Pontiac Grand Prix GT Sedan. 3.8 liter 3800 Series II V-6, automatic transmission, approximately 82,000 miles. Fuel Injection, 4 wheel disc brakes with ABS, Enhanced Traction System, front wheel drive, power rack-and-pinion, air conditioning.

The problem that I am having is my Service Engine Soon light keeps coming on, then goes out after it resets itself (after so many times of turning the car on and off). When I am driving usually at higher speeds, but not all the time the car seems to hesitate when I accelerate. Some times it is so bad the entire car starts to jerk forward and back. When on the freeway and I step on the gas the car seems be slow to accelerate.

The code that the dealer pulled up is P0300 #1 Misfire and told me to change the fuel filter, put better gas in the car and use some fuel injector cleaner in my gas. Well I did all that, I use nothing but Chevron High Octane (With Techtron) gas, have used two fuel injector bottles in my gas and changed the fuel filter (the one under the hood) still doing the same thing. Took back to the dealer and the same code appears and they told me they don't know what is wrong. I was wondering if you might have an answer for me?

Thanks,
Dan

A. You say a fuel filter under the hood?? The fuel filter should be under the car near the fuel tank. If it was clogged you would have a severe hesitation and possibly all cylinders showing a misfire. I can't believe a dealer can't solve this. You need to look at all things associated with #1 cylinder. Spark plug cracked? Wire bad, injector, compression test. There are lots of things for them to check before they say they can't find a problem.

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