I have a 94 Gt with aode and bolt on mods but mostly stock. Under load with pedal all the way to the floor the engine pings really bad, then i let off and it runs fine. I have a vaccume gague and it starts pinging at around 4 pounds all the way to zero when pedal is on the floor. What the hell is going on? thanx for any info!

 

i bet you have your timing advanced and your running ****y gas? i'd check there first

 

you're prematurely ejac...err... detonating.

run premium, 91+ octane.

 

Timing advanced too far causing preignition? Rod knocking?

 

when you hear pinging, its the pistons rocking back and forth inside the cylinder due to the gas igniting prematurely, also if your running cheap gas sometimes hot carbon build up will ignite it too, use higher octane so its harder to ignite[sm=smiley20.gif]

 

Ya i use the mid chevron octane, so maybe it is the timing, it should be 13 degrees correct?

 

I would also check to make sure your crank pulley hasn't spun.There seems to be a rash of that going on lately.Set motor at TDC and make sure timing mark shows correct.

 

No the pinging you hear is two separate flame fronts impacting each other in the cylinder.


And if you live up in colder climate locations (below freezing most of the winter) then you will get some heavily "winterized" gas which is more likely to ping. Also in colder weather the ecu adds (or doesn't pull) as much timing due to the cooler intake temps. Run some higher octane gas or octane booster that should help - also only gettin gas from places like Shell & Chevron

 

Run some VP C12 though it and see what it does....

 

just re set your timing and run preminum only. if you cant afford it set timing to 10.