pre-ignition problem

[LittleRay]

I have been chasing a pre-ignition problem for two years now, HELP!!!! I have a 95gt that is a total pig. When the car is cold or it is winter the car runs great but when it warms up outside the car loses a ton of power and picks up a horrible pre-ignition. the only mods to the engine itself are adj fpr, pulleys, and exhaust. The timing is set at 10 degrees and the fuel pressure is set at 35lbs. We have messed with both extensively and no gain. this is our first time messing with the 95 and all the foxes I have had never gave me a lick of trouble. The plugs are stock heat range and we have varied that as well. is there any problems with cu, sensors, tps, or anything that is specific to the 94-95 that i am not aware of. I would greatly appreciate any help I can get!!!!

 

[Paul]

The problem is the timing/fuel maps in the 94-95 ECU leave something to be desired. On a few of my near-stock 94-95 GTs, I've been able to reduce pinging but not eliminate it completely. I put plugs one heat range colder in, set the timing at 8-10* initial, and set FP to 41 with the vacuum line disconnected. That seemed to help a bit.

Paul.

 

[ryclef331]

Your fuel pressure is a little on the low side....bump to 39-42...make sure you're running the highest octane you can. get back to me then.

 

[LittleRay]

we ran the fuel pressure at 40lbs forever and I only run premium in the car. fuel pressure made no difference

 

[ryclef331]

Is the car throwing any kind of codes? Sounds to me like the EGR may not be properly functioning.

 

[Paul]

+1 If your EGR is not functioning properly, that will increase like the likelihood of pinging.