94 GT pinging, help please

I agree. I will try recording it inside the vehicle, just to let you guys hear it. But I was trying to pinpoint the noise with the recorder, though that may not be easy or even possible.

It is a relatively faint noise from inside the vehicle. I have heard spark knock at 3000-3500 rpms and it sounds louder and absolutely horrid. Just not sure if this is a different type/level of spark knock or what.

The way I can describe it is the 3000-3500 rpm pinging I heard sounded like putting a big bolt in a metal paint can then shaking it up and down abruptly and harshly.

The low rpm "pinging" I hear sounds like coins or keys jiggling in a pocket. It definitely sounds more metallic than air-like.

I will get to recording it from inside - thanks. Also, I live in Kirkland, WA.
 
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Alright, here's my best attempt to record the noise. I'm not 100% sure this is the pinging noise I am hearing, but I am pretty sure it is as this noise was occurring significantly under load conditions.


94 Mustang GT pinging noises under load/low rpm - YouTube

As the video description says,

This sound clip is recorded from the strut tower brace right next to the EGR valve.

Noise is heard best from 0:02 to 0:07 and 0:24 to 0:28

Remember, I do not hear this noise unless under load or accelerating in low rpms.
 
Here's a video of the fuel pressure while driving. Max speed was like 30 mph and max rpm was like 2500-3000.

Sorry the video is crappy quality and there's no rpm gauge, but I added video annotations to try to help.

I honestly don't know what the gauge should look like while driving. Only thing I really noticed is that the gauge shutters a little bit somtimes when I hold the gas pedal down.

94 Mustang GT fuel pressure while driving - YouTube
 
Here's a new video I recorded by attaching the recorder to the fuel lines under the car behind the passenger side front wheel.

I think you can hear it better than in the other video of the sound from the passenger side strut tower brace. In fact, I think that sound may have been completely different. But I know for a fact the sound recorded below is what I've been hearing.

94 Mustang GT pinging recorded from under car - YouTube
 
Adam, the sound in the first video is something I haven't heard on this car before. I think it *may* have been the recorder's case tapping against the brace.

But the video I just posted is definitely of the sound I am hearing.

Tomorrow I will see if I am able to mount the recorder in around the same spot under the other side of the car (might be hard since there aren't fuel lines over there) and see if it is as noticeable as on this side. Hopefully using this technique I can narrow down the relative source of its occurrence.
 
Adam, the sound in the first video is something I haven't heard on this car before. I think it *may* have been the recorder's case tapping against the brace.

But the video I just posted is definitely of the sound I am hearing.

Tomorrow I will see if I am able to mount the recorder in around the same spot under the other side of the car (might be hard since there aren't fuel lines over there) and see if it is as noticeable as on this side. Hopefully using this technique I can narrow down the relative source of its occurrence.


Thats a possibility. Im hearing nothing that sounds like pinging. Even when im trying to hear something all i hear is possibly an unconnected smog pump tube and maybe an exhaust leak...

But seriously its like shooting in the dark with that video for me. Maybe i dont have good speakers.
 
Yeah I know man, it is a bit hard to hear it. I have to turn my speakers up to hear it well. Unfortunately it's very difficult to isolate the sound even with audio editing software and such.

I really do appreciate your guys help so much.
 
I don't think you are pinging.

I think you are hearing simple valve chatter in the exhaust because you are bogging it.

Install 4.10s and gt back to us.

You can also run a spout connector out test.
 
I'm in Seattle, WA

Recently took it to another mechanic (local, this time), who seemed quite knowledgeable about cars. I had my manual transmission fluid changed for the first time since it was new (82k miles now).

He and I took test drives together and shot ideas back and forth. He thought the sound sounded rotational. He thought u-joints, but I told him I believe I've heard it at idle if I drop the RPMS low enough (by taking the SPOUT out), so that couldn't be it. I asked him if it sounded like engine internals and he said that it doesn't.

Obviously I've ruled out the pulley system as I've gotten it to happen just as badly without the belt on.

He said that if it was his car, he wouldn't even worry about it.. probably wouldn't have even noticed it.

Still bugs the heck out of me though.

I'm leaning toward the sound coming from the engine itself (but keep in mind it can be heard best from under the car), something to do with the exhaust, or maybe something to do with the front of the transmission.
 
My 94 GT with 81500 original miles has been pinging for a few years now, or about 3000-5000 miles. It's stock minus a JLT cold air intake and a flowmaster cat-back exhaust.

When I first began driving it about 4 years ago, I did not notice it at all, so it appeared to begin happening suddenly.

The pinging occurs at nearly any rpm if the engine is under load. It will happen from 800+ rpm when I get going on flat ground in 1st gear. I don't hear pinging when I'm cruising at a steady speed on flat ground. It will also ping regardless if it's 40 degrees out or 90 degrees out.

I have aggressively searched google and tried several things to fix it, including:

- Running 89 octane currently (running 91 doesn't seem to help any.. also note: contains up to 10% ethanol)
- Had shop replace broken EGR system (so it is supposedly fixed, it was broken)
- Replaced fuel filter <3000 miles ago
- Cleaned MAF sensor with MAF cleaner
- Replaced ACT sensor
- Replaced ECT sensor (was getting CEL code 116)
- Changed platinum autolite 25 plugs to copper autolite 24's (one step colder) and gapped them correctly (were gapped incorrectly at .042 rather than .052)
- Replaced cap and rotor (wires are relatively new)
- Ran a couple rounds of seafoam through a vacuum line (didn't get much smoke)
- Retarded timing from 8* to 6* (didn't seem to do anything really)
- Checked and found balancer is NOT spun
- Checked fuel pressure, is 32 psi w/ vacuum and 40 psi w/o vacuum
Since I started this thread:
- Replaced PCV valve and PCV filter (was really gunked up)
- Reinstalled factory air cleaner to see if the CAI was causing issues. The switch didn't change the pinging.
- Tried 89-octane ethanol-fee gas (assuming the station still sells ethanol-free), and noticed little to no difference
- Changed o2 sensors - might be noticing some improvement. Only took for a short drive and maybe it takes some time for the computer to adjust to them?

The last mechanic that I went to (who replaced the EGR system) said it could not be fixed because of the ethanol that is put in gas these days. However, I will not take "no" as an answer - I believe it can be fixed.

Does anyone have any ideas on what is causing it? If more elaboration is needed on my part, I'd gladly do so.
Did you ever fix this problem
 
I agree. I will try recording it inside the vehicle, just to let you guys hear it. But I was trying to pinpoint the noise with the recorder, though that may not be easy or even possible.

It is a relatively faint noise from inside the vehicle. I have heard spark knock at 3000-3500 rpms and it sounds louder and absolutely horrid. Just not sure if this is a different type/level of spark knock or what.

The way I can describe it is the 3000-3500 rpm pinging I heard sounded like putting a big bolt in a metal paint can then shaking it up and down abruptly and harshly.

The low rpm "pinging" I hear sounds like coins or keys jiggling in a pocket. It definitely sounds more metallic than air-like.

I will get to recording it from inside - thanks. Also, I live in Kirkland, WA.
Hi I was just wondering did you ever figure out what this was because I have a 2003 mustang V6 and it is pinging at lower RPMs when the engines are load everything else I've took it to the shop they try to tell me something about $8,000 that's all I heard. Just can't figure this out and I was hoping praying that you found something out about yours and maybe I can try to see if it works in mind I don't know please let me know you can email me at [email protected]