since last year i was going to be late to work so i drove it on empty and on my way home from work it ran out of gas, started shaking pretty bad turned off, then went and got some gas and went i tried to turn it on started shaking again and then went back to normal , or so i thought. ever since then everytime i rev it to a high rpm when i let off it the exhaust starts popping sounds like popcorn popping. ive tried replacing fuel filter, plugs wires, knock sensor and wiring, cleaned injectors, checked fuel pressure looks good, dont know what else it could be. they ran a diag check on it and all that came out was knock sensor codes so thats why i replaced both of them and its wiring... any ideas?

 

You may have tried to clean the injectors but they can still be dirty. If you changed the fuel filter and all that other stuff maybe you ran it dry and sucked up some serious crap and the injectors are clogged.

When you're on the gas the fuel pressure will usually overcome dirty fuel injectors, but at idle or when you let off the gas pedal that pressure drops and the fuel starts getting cut off.

Just a thought, maybe take them out and check them.

 

one thing i forgot to mention i just replaced the knock sensor wiring this weekend and barely read how to reset the pcm so i did that today dont know if it`ll make a difference

 

Lots of threads on this. Its a common thing and my car has done it on cold starts ever since coming from the factory. The fix is to not rev the engine until the car warms up.

 

thats one thing i forgot to mention i could be driving it all day and it`ll still do it, i guess ill look into cleaning the injectors again

 

wow, did the pcm reset and about 95 percent of the popping is gone, all i hear now is the regular rasp like before 8-) , ill just try cleaning injectors and hopefully it`ll all be gone, thanks everyone

 

about to give up, well the rest helped for awhile but then it came back. replaced injectors, still nothing, im thinking maybe when we replaced the knock sensors we over torqued them. running out of ideas.. anyone ??

 

Usually that popping sounds is related to too much timing in the tune.

You didnt list mods, tuning or anything - so I dont know if its stock or not.

Resetting your PCM plays into this somewhat.

If the car and tune are stock, might want to have a GM dealership reflash it.

If it was tuned, I'd go and get the tuner not just re-flash your tune, but to go and re-tune the thing all together.

 

yeah the car is stock, after i took it in for a diagnostic check he asked if i overtorqued the knock sensors wasnt sure about that but he also said that it might need to be reflashed like you said, do you know how much it costs to get it reflashed at the dealership?

 

Probably around $75. It'll be the latest revision from GM.

Aside from the tune, you seem to have nailed eveything else I can think of, and that others have posted.

I dont know how tight money is, but even a stock LS1 benefit in HP and performance with a real-time dyno tune. They usually run about $200 - $300.