PING!! KNOCK!!! HELP!!!!!!!!!!!

[mustangman9494]

My 1994 mustang GT has been ping for the last 4 months and I can't stop it. It really only pings when the engine is hot. If the engine is cold it hardly pings at all. I think it might be the MAF, but I don't know where to get one. And if it is cold I just get a Cold Air Intake without buying a new MAF. Any help on these questions or any thoughts on this subject would be more than apprecitated.

 

[94TURBO5 O]

You can pull your spout out and set your timing @ 20-24 for a cheap fix and it will stop until you get the problem figured out.

 

[Rootus]

What's your base timing at?

 

[mo_dingo]

You can pull your spout out and set your timing @ 20-24 for a cheap fix and it will stop until you get the problem figured out.

He is 100% correct. But like he said, only a temporary fix.

You say that it only pings when the car is hot. We need some more information.

You need to run some tests first. Get the car bone cold. Start the car, and quickly find a "strip" to make a test run. I mean quickly. The car gets to operating temperatures very quickly.

So, you are at this "strip", and the car is bone cold. Nail it all the way through 2 gear, and halfway to 3rd gear. Make sure the pedal is on the floor. Does the car ping now?

Now, let the car warm up. Once the temp gauge gets to it's normal spot, you can begin further testing. Put the pedal all the way to the floor(VERY IMPORTANT), and go all the way through 2nd gear and part way through 3rd (up to 70mph is sufficient). Does the car ping now?

Let off the gas completely, but stay at 70 mph. Now, in 3rd gear, accelerate the car, but [size=+1]NOT[/size] at full throttle. 1/4 to 1/2 is good. Does the car ping now?

After you run these tests, you can start to figure out which sensors, if any, are the problem.
Scott

 

[mustangman9494]

Thanks for the info so far. ME and my dad set the timing way way ahead and that didn't fix it. And it pings all the time. When the engine is cold it starts to ping at about 2500-2700rpm. And when the engine is warm it pings at about 1800-up. The pinging starts off not that loud, but up around 2500 it sounds like the pistions are just going to explode it is so loud. I don't know exactly what to do. Right now I'm just checking sensors, but it is hard to tell if they are working. So far I tried the MAF and the IAT sensor but I can't tell if they are working good or not.

 

[Rootus]

Couple of things:

1. "way way ahead" means how much timing?

2. Why are you sure what you are experiencing is pinging?

Dave

 

[mustangman9494]

Way way ahead, if I remeber what we had it was between 20-30 degrees. And I don't know what else it could be execpt pinging. And suggestions would be helpful!!!

 

[Rootus]

20-30 degrees base timing, or did you leave the spout out? I assume you've reset it to 10* and put the spout back in? And you've tried backing the timing off some more just in case the balancer is spun?

Is it pinging full time, or just at WOT or while under heavy load?

 

[mustangman9494]

You said, "Is it pinging full time, or just at WOT or while under heavy load?"

It pings all the time driving unless you keep it under 2000, and I don't know what WOT means (actually I probably could but its to late right now), and it doesn't ping in neutral when you rev it.

 

[Rootus]

Okay, then I guess I think it's not pinging, OR your timing is way, way too far advanced. Pinging generally happens when 1) the motor is very hot (like overheating), and/or 2) under heavy load (lugging up a hill in a high gear), or 3) when at WOT (wide open throttle).

If you're getting "pinging" at part throttle, low-load, then I would suspect a problem more mechanical in nature.

If I were you I would begin by verifying exactly where your timing is right now, and then if necessary setting it to 10*. If the stock balancer has spun, then the timing marks will be completely wrong and not usable. The easiest solution to that would be to get a new balancer. Finding out if the stock one has spun is a bit of a chore.

Dave

 

[HISSIN50]

i did not read all this, so i might have missed something. i would take the car back down to stock timing. leave the spout in (he can take it out later). run codes.
see what gives with stock timing and codes.
good luck.

 

[mustangman9494]

anyone else??

 

[94TURBO5 O]

Have you tried leaving the spout out and 20 degrees timing yet?
All I can tell you is I ran the spout out for 2 months with the blower and it stopped pinging/detonating. I put on a smaller blower pulley and put in the spout on the dyno and lost my HG. I replaced my HG and left it out and it never pinged again. I put in the spout to go get it tuned last week and it blew the HG again on the way from detonation and I had my base timing set @ 8 degrees. I just fired my car up last night took it for a spin with 15 degrees locked timing and it feels like a beast w/ no pinging.
Just my

 

[mustangman9494]

Thanks I'm going to try thay.

 

[RedHot91GT]

Is the timing different on the sn95's than on the fox's? because on our cars I always thought you took out the spout to set the base timing, then you put it back in and the computer takes over... Is it different on sn95's?

 

[HISSIN50]

Is the timing different on the sn95's than on the fox's? because on our cars I always thought you took out the spout to set the base timing, then you put it back in and the computer takes over... Is it different on sn95's?

i think it is a little different (fellow AZ fox guy here - not an SN guy). SN's have a lot of issues with pinging. seems that the smaller front profile (nose) creates less cooling, as well as a lot of puter changes (why some SN guys run A9L puters), etc. they get a lot of pinging issues with MAF's being dirty too, it seems (does not seem like fox MAF's are so sensitive).
real SN guys, does this sound right? i dont know half what some of you folks do about the ideosynchracies of you cars - just my two cents.

 

[HISSIN50]

oh yeah, forgot the point. since they have detonation issues, a few guys lock out the timing. some fox blown guys do the same though - might be more characteristic of blown cars rather than fox vs SN's.

 

[Bad Saleen]

My pinging was resolve with the help of JR i took the spout out and set my timing at 28*, i gain 2 tenth second on quarter mile and never hear pinging again


This rock

 

[94TURBO5 O]

mustangman: So what's the deal? Did it work out for you?

BAD Saleen:
Glad you fixed the prob and shaved some time off.

 

[chrismillion]

You can pull your spout out and set your timing @ 20-24 for a cheap fix and it will stop until you get the problem figured out.

you should ask Vib to put that on the FAQ board because someone asked that everyday.