Detonation: Lean or rich condition?

[Tony91Sport]

Ive got a bad problem with my car and detonation. Its so horrible, I hear it whenever I accelerate hard. I was always under the impression that detonation is a lean condition. Someone told me it had to do with timing too, but I cant adjust the timing(damn computer). Anyway, what can I check to make sure my engine is getting enough fuel? Im going to bu a fuel pressure tester tomm. Could a bad fuel pressure regulator cause this? If it was broken id think it would be getting too much fuel. Well anyway mine has never been replaced, and I hear so many people say they have problems with them.

 

[sink]

Predetonation (ping) is a condition brought on by either three things. 1. Mixture is too lean and timing is fine. 2. Mixture is OK and timing is too advanced. 3. You were running too rich and built carbon that is lighting off the mixture early as the compression comes up. My 94 XLT ping got fixed when I cleaned the MAS. Try that. The computer thought that I was getting less air becaue the MAS filaments were insulated by crap. Then it gave me too lean a mixture. It pinged like mad on any light load. Two separate dealer service's didn't catch that one because it gave no magic codes to the computer. Those idiots. Too many of them couldn't diagnose their way out of a paper bag.

 

[Tony91Sport]

I bought a new MAF, cause I cleaned the old one and it didnt help. I also had the fuel pump and the relay replaced, but its been happening long before that, so I can eliminate those.

Tony
91 Sport 2WD

 

[sink]

Tony, your name changed! Good luck on that ping- it can be annoying.

 

[Tony91Sport]

whoa, my name changed to the old one. I meant ive already installed the MAF with no luck.

Tony
91 Sport 2WD

 

[MOTO MIKE]

tony..... have you changed the oxygen sensors yet??? this could also change the air fuel ratio causing predetonation...... also.... what temp is youe exp. running at??

 

[Tony91Sport]

I changed the O2 sensors not too long ago. I dont quite remeber. However I bought a timing gun today, and the mark is way above the advanced mark, like 1/8th of an inch. From what ive read here, isnt there a switch behind the headlight that will mess with the timing? If it retards the timing I may be in luck. I thought the engine might not be getting enough fuel, but im going to try to fix this first.

Tony
91 Sport