96 Gm 5.7l Detonation On Hot Starts?

[Valvetrain]

Hi, I have 1996 GM yukon 5.7L that always detonates on start-up when the engine is hot. It drives me crazy! I have been trying to solve this issue for a while now. Higher octane fuel doesn't work. I don't want to start dumping money into this thing but I want this resolved. I thought about installing another oil cooler and electric fans that kick on when I shut the motor down. But sometimes I hop right back in my truck after a minute and start it back up, if I'm at the gas station or something. So far everyone I've talked to about this say there is nothing you can do. But i know there is. I really think richening the mixture at start up will help. What do i need to do this? A Hypertech chip with computer controlled adjustments or something? Or can i just adjust the ECU? Any ideas would really help! If you think I'm off base and its a problem that I am overlooking please let me know. Oh and all my fuel injectors and O2 are fine.

Thanks

[bill190]

Have you tried checking all the things listed in the GM Factory Fuel and Emissions Service Manual for driveability symptoms: Detonation/Spark Knock?

 

My book has two pages of things to check/test for this symptom.

[Valvetrain]

Im gonna answer my own question and say I think we should be able to adjust our own air/fuel. Emission is a very good point. I doubt a new charcoal will help either as fords do not exhibit this behavior when bad.

[redvett]

I would guess its carbon in the combustion chamber. Try a top end cleaner.

[Valvetrain]

Thanks for the replies!