engine ping

AZSnake98

New Member
May 18, 2005
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i have a 94 GT with roughly 115000 miles on it. At higher RPMS when its about to shift (automatic) a metallic rattle occurs. It seems to get worse when i have less gas in the car. Ive changed the timing and this helps a little.. but doesnt cut it out completely. Ive checked for unmetered air and the intake has no leaks. The only thing i can think of is the vacuum lines... anyone know anything else that can cause detonation or engine ping?
 
i've got the same problem only with a manual trans, i've gone through all my basics and even replaced my maf last weekend and it made a bit of a diff but didn't cure it. i'm going to check fuel press this weekend and if its ok then i'll change my o2's and when that doesn't work i'll change the pcv valve. does it go away with diff fuel and how much oil do you burn as oil entered into the combustion chamber lowers your octane rating.
 
Ive tried better gas too and it makes a little bit of difference... but it just comes back.. i want it to stop!!! i dont just wanna make the sound go away... i wanna find out what it is and fix it... it could become serious if left un-fixed..
 
it sounds like your FP's are on the way out. the highest demand for a FP is at high rpms. if you can do it, hook up a pressure gauge and drive it (has to be under load) while an assistant watches the FP at the time it pings.

Good luck.
 
yeah sounds like your pumps almost done for sure, if it runs better with a full tank then a low tank then thats pretty much your problem.

I dont see why it would PING, studder yes. You sure you have the right octaine for your timing settings?
 
when the pump does not deliver enough volume of fuel at high rpms, that leads to leanness, which results in pinging. :)
 
The ping thing is caused by Ford making the GT's pcm values to where the fuel is so lean and the spark is so high that even when everything is like it should be......you are very close to conditions that cause ping.

Thats why some of our cars have pinged from day one and some peeps can't seem to kill it.

The fuel and spark is much better on the Cobra pcm and thats the reason you don't hear the Cobra boys cry about ping.

Later
Grady
 
i've had the problem since i bought the car 20k ago... on the stock exhaust set-up i could tell easily... with the cat back it was hard to hear it at high rpms... and now with the o/r H i couldnt hear it if my life depends on it... so i just load up on 93 and i turned my timing down to 11*... i tries running up to 14* before but 14, 13, and 12 all led to ping, so im thinking maybe it is a fuel pump.pressure problem... us GT's are just cursed with a shady puter...
 
i recently started cruising at around 1500-1700 rpms to save gas. when it is like that, i get sime detonation if i open the throttle too much.

i just went to 89 octane, it is too early to know if it is better.
 
I cleaned my Mass Air Flow Sensor with rubbing alcohol and a couple q-tips and my ping problem went away completely. Along with gaining like 30HP..Im willing to bet if you cleaned yours, you would have the same results. If there were ever more true words spoken... CLEAN YOUR MASS AIR FLOW SENSOR.
 
BlackVert said:
i recently started cruising at around 1500-1700 rpms to save gas. when it is like that, i get sime detonation if i open the throttle too much.

i just went to 89 octane, it is too early to know if it is better.
Just a question for someone considering getting a TwEECer. Can you not take care of this issue with the tuner?
 
HISSIN50 said:
Just a question for someone considering getting a TwEECer. Can you not take care of this issue with the tuner?

Sure you can!

You have access to the spark/fuel tables which give you the ability to adjust various load conditions at various rpm's.

Later
Grady
 
final5-0 said:
Sure you can!

You have access to the spark/fuel tables which give you the ability to adjust various load conditions at various rpm's.

Later
Grady
I thought you could, but was not sure what the issue was (I saw a TwEECer in his sig). Thanks bud! :)

BTW, we gotta chat one of these days (I did not forget - just crazy busy of late. :bang: ). :nice: