WOT pinging/detonation

[Josh94gt]

My car has been pinging lately. It only does it under load at WOT that I've noticed so far, and it kicks in at about 3000rpms and continues up to redline. I put in some 89 octane while driving cross-country and that seemed to help some. It also seemed to happen less at night when it was cooler. What should I be checking/cleaning/replacing/etc. to track down and fix this problem??? It just had plugs/wires last year.


-Josh

 

[saleener94]

Seafoam/Napa auto parts

 

[DaveB]

When was the last time you had a tune up?

 

[HISSIN50]

Pull codes. If you can, monitor FP when this occurs. Clean the MAF wires, the IAT, etc.

Good luck.

 

[1TallMF]

Do you know what the base timing on the distributor is set at? Try bumping it down a degree or two if its set above 10*. Cleaning the MAF sensor is always good to do on a regular basis as well.

 

[gcomfx.com]

Drop timing, add better fuel, or bump the fuel pressure. The choice is yours. You might also check your plugs. If they are old and the gap has opened up it'll do this.

 

[95BLKGT5.0]

I had the same problem and cleaned and replaced anything that would cause it.
Any of the solutions everyone has said could be it (except bumping the fuel pressure). Its just the opposit on fuel pressure and that was my problem. Fuel pressure should be 39 PSI (for a stock car with stock 19# injectors)with the vacum line disconnected and pluged at he fuel pressure reg. After adjusting the fuel pressure disconnect the battrie for 30 min to clear the computer. Then take the car out and drive it like you would normally.

I did that after getting fustreted at the pinging and took it to "The Mustang Shop"
They adjusted the fuel pressure to 39 PSI undid the bat. and after 30 min we took it for a ride and it was like a new car. Pulled harder in 2nd,3rd and 4th gear then it ever has, it was like a new car.

 

[gcomfx.com]

Except bumping the fuel pressure. LOL Yup, I don't know what I'm talking about. While his fuel pressure might be stock. One should never assume so.

I've successfully sprayed 125 shot of dry nitrous on a stock engine for over 6 years with 89 octane in the car on occasion. Trust me on experiencing pinging and detonation. The only casualties of war.... stock balancer, and ONE spark plug.

I left my timing at 6* all the time. The only adjustments I could make easily was the octane in the gas and change the fuel pressure.

 

[HISSIN50]

I had the same problem and cleaned and replaced anything that would cause it.
Any of the solutions everyone has said could be it (except bumping the fuel pressure). Its just the opposit on fuel pressure and that was my problem. Fuel pressure should be 39 PSI (for a stock car with stock 19# injectors)with the vacum line disconnected and pluged at he fuel pressure reg. After adjusting the fuel pressure disconnect the battrie for 30 min to clear the computer. Then take the car out and drive it like you would normally.

I did that after getting fustreted at the pinging and took it to "The Mustang Shop"
They adjusted the fuel pressure to 39 PSI undid the bat. and after 30 min we took it for a ride and it was like a new car. Pulled harder in 2nd,3rd and 4th gear then it ever has, it was like a new car.

Had you tried disconnecting the battery before jockeying with FP? I dont see how the extra FP would have hurt anything or caused a lean issue. Now having adapted into some kind of lean tune due to a bad sensor or something else did seem more likely (and clearing the KAM starts things over fresh).

I simply had to ask because it's indeed a counterintuitive fix (we all know the adaptive control largely negates any FP changes with time, which makes it even more curious).

 

[illwood]

Another possibility is the ECT sensor that sticks out of the tube in your intake. If the computer doesn't know the temp of the engine, it will call for innapropriate timing.

 

[Josh94gt]

OK so yesterday I pulled the MAF and it was BLACK!!! I cleaned it with a few q-tips soaked in rubbing alcohol (that worked GREAT) and now it's a nice shiny metal silver color again. When I reconnect the battery to start it back up again, what should I do to get the computer to re-learn everything again? How long shouldI let it idle, drive normal, drive harder than normal, drive for the sole purpose of destroying my rear tires, etc?

-Josh

 

[HISSIN50]

Josh, just drive normal IMHO. The puter will simply need to see a range of driving situations to dial itself in. If you drove other than normal, then when you eventually drove normally, it would simply readapt anyhow.

Good luck.

 

[nickgt5.0]

mine was doing the same thing and it took me forever to figure out. My timing was at 19*. time it down to 13* and its perfect now.