2002 chevy Silverado LT extended cab 5.3l 2wd p0300 code

Question

I get a p0300 code when driving above 50 mph going down hill. The code will set after going down hill several times or for a long enough duration to set the code. I have no symtoms with this. The sevice engine light blinks going down the hill and goes out going up hill or on flat ground. Once the the code sets and the light stays on it will blink going down any more hills. Driving around at slower speeds even going down hill it never sets a code. The intake manifold gaskets have been replaced with the newer type in an attempt to correct this code being set.

Answer 1

Hi there,

This code indicates misfires on random cylinders. Here is a list of possible causes.

P0300 CHEVROLET - Cylinder Misfire Detected Random Cylinders

Read more: https://www.autocodes.com/p0300_chevrolet.html