how can you tell if theres spark retard and knocking?

Question

I have a 99 GTP

Answer 1

I think I understand your question.....

If while under "moderate" throttle, it will sound like there are marbles in your engine.


A better question, would get better answers.

Answer 2

The knocking will be the 'pinging' sound when the engine starts to load up as you start up a good hill. This could be the octane of gasoline you are using. I am not sure what octane this vehicle is suppose to use.

As to the spark, check it with a timing light. Both the 'pinging' and spark problems may be related. Late firing causes 'pinging'.