the engine is giving me detonation at mid to full throttle when going from normal cruise to pushing ,like to pass ,or from when you first start out and trying to get up to speed in a quick manner.it's only got 54000 on it,i've never touched the ignition timing either..... any suggestions?????

 

Assuming no change in timing, check your EGR system, valve, etc, if it fails or plugs up, you're going to ping badly. Also make sure your fuel pressure to the injectors is good, running lean will also cause detonation. Insufficient EGR gas flow should set a code in your ECU, you might want to see if there's any codes stored in there.

 

I have seen this cured many of times by spraying a can of carb cleaner into the vaccum line from the brake booster. This will remove a bunch of carbon from the piston tops and the back of the valves. It really seems to work. We had a special bottle and chemical at the lube rack that I worked at and we charged 50 bucks for the service but the carb cleanre works just as well.

 

thanks alot,i'll try it... i had a 93 f350 and it never gave me a ping unless it was pissed off and it took alot to do it.useulally pulling hard at lower than usuall rpm's. 460's are awsome

 

 

How much carb cleaner are we talking about putting in the brake vaccum line and is it running when you do this?

My '88 460 has started to ping. I put 93 in it and checked the timing - nothing. I did replace the EGR valve recently, but I would have thought that would help, not hurt it.