2008 Pontiac Grand Prix 3.8L My car has a P0300 diagnostic code. Check engine light is on, and typically flashes if I exceed about 30 miles an hour. How can I fix this?!
I have changed my ignition coils,
cleaned my throttle body, egr valve,
and added a bottle of fuel injector
cleaner into my last tank of gas.
Worked fine for about a week and
started again. It has an occasional
low rough idle, and loss of power.
And has bucked on me a couple of
times. I am thinking it may be a
timing belt issue or a camshaft
position sensor. I am just trying to
figure out my next step. Please
help!!!