Pinging

[pinhye]

I have had a problem with spark knock, high rev/WOT pinging without a clue on how to fix.

I lost my ignition pickup and had to replace the distributor, so I changed the module too. I had the problem before these changes but had more of the problem after. I had the car tuned to factory specs and went back to 89 octane gas, same problem.

I took the car to another garage to have a look and they ended up changing the timing to 5 degree TDC.

Now no pinging, even at WOT.

Has anyone had this problem? The mechanic thought it could be that the harmonic balancer slipped or even the timing belt slipped. The engine is otherwise sound (good for having 117K miles).

Eric

 

[95CobraMike]

Harmonic balancer cannot slip...it has a key on the shaft.....there is no timing belt on your car, its a timing chain....and cannot slip

solution = Find a new mechanic

 

[95BLKGT5.0]

Harmonic balancer cannot slip...it has a key on the shaft.....there is no timing belt on your car, its a timing chain....and cannot slip

solution = Find a new mechanic

Very well said!

 

[pinhye]

Harmonic balancer cannot slip...it has a key on the shaft.....there is no timing belt on your car, its a timing chain....and cannot slip

solution = Find a new mechanic

Okay Mike. Point taken.

Even with all that said, it doesn't explain why the car pings hard when timed at 10 degree TDC and doesn't ping at 5 degree TDC. Is there something in the electronics that would cause an extreme timing advance during heavy loading, like at WOT or pulling a hill, etc...

 

[94TURBO5 O]

Harmonic balancer cannot slip...it has a key on the shaft.....there is no timing belt on your car, its a timing chain....and cannot slip

solution = Find a new mechanic

Your mechanic most likely works on RICERS b/c no intelligent person with an ASE would know a 5.0 V8 has a timing CHAIN. You need to have a serious talk with him and re-check your timing and anything else he's worked on for you.

You are getting this from a # of things or just 1. Your sensors like the IAT, IAC, ECT, MAF could be old and malfunctioning giving the EEC in correct readings. Your petro selection could also be the culprit. Yeah everyone doesn't need to run 93 but sometimes 89 depending upon where you get it could be just low in octane. Try an Octane Booster and see if your problems are cured after re setting your timing back to 10-14*. The top of your pistons could be layered in carbon deposits also cusing pinging, and you can yank the heads and clean them or sea foam like a lot of people do on here.

There are other things and I'm sure everyone will soon chime in.

 

[94TURBO5 O]

One more thing you can do to stop the detonation but it is used as a "band-aid" so to speak but will cure it for sure. Set your timing @18-24* with the spout out and then leave it out, that's it. You have now "Locked" timing and it is perfectly safe and all it does is take the timing advance control from the EEC. Meaning it doesn't allow the EEC to advance timing at will and your timing stays "locked" at whatever degree you have it set. I blew 3 sets of HG's from boost b/c of the EEC advancing and I locked timing and never detonated again. I ran it like than for 1 year then bought a P.M.S and it cured the problem. You'll be running timing like a non EEC motor. Try it and let me know.

 

[95CobraMike]

sorry for not also listing a solution....
umm i would recheck your timing, who knows if he did it right??
did he take the spout connecter out when he set the timing to 5 degrees? or did he set the timing to 5 degrees with it in? that would mess it up..and considering he thought the HB could slip and there was a timing belt.....probabaly would check.

 

[pinhye]

Your mechanic most likely works on RICERS b/c no intelligent person with an ASE would know a 5.0 V8 has a timing CHAIN. You need to have a serious talk with him and re-check your timing and anything else he's worked on for you.

You are getting this from a # of things or just 1. Your sensors like the IAT, IAC, ECT, MAF could be old and malfunctioning giving the EEC in correct readings. Your petro selection could also be the culprit. Yeah everyone doesn't need to run 93 but sometimes 89 depending upon where you get it could be just low in octane. Try an Octane Booster and see if your problems are cured after re setting your timing back to 10-14*. The top of your pistons could be layered in carbon deposits also cusing pinging, and you can yank the heads and clean them or sea foam like a lot of people do on here.

There are other things and I'm sure everyone will soon chime in.

The mech didn't use 'belt', I did. And won't make that mistake again. This guy seemed knowledgeable and came recommended. He had more good ideas to fix the problem then the past two or three.

The timing has been played with for quite some time, each time not correcting the ping until this last adjust to 5 degrees.

Have you heard of a machine that will clean the carbon build up? This mech told me that the carbon might be a problem and so recommended I have it done, which I did.

Is there any electronic checks that could be used to isolate if a sensor is bad?

 

[94TURBO5 O]

OK cool. Have me blasting the guy for no reason.

You can go and buy a code scanner for 25 at Wal Mart and run your codes. Try cleaning the MAF with alcohol and a swab and do it gently. Do the same with your IAT in the inlet air tube after the air box. All of them are under 20 each to replace.

 

[95CobraMike]

SEAFOAM!!!!!! $4.99 at auto zone cleans out the carbon build-up
takes about 10 min works great!

 

[pinhye]

Can using this cleaner harm the internals?

Since the car has 117K miles, should the sensors already mentioned be replaced with OEM.

What is this code scanner going to show me?

 

[RFMustangGT]

Harmonic balancer cannot slip

yes it can in it's own way. there is a pressed on part that has rubber between it and the hub. I had a problem with getting my car timed after I worked on it and also had a bad vibration. the outside hub with the timming marks can slip causing problems. it's not a common thing but it does happen. I had a guy who races in fun ford weekend modular maddness class fix mine. he showed me the balancer and it was a two seperate parts: the part that bolts to the crankshaft and a pressed on outside hub which does the balancing and used for timming. mine had the rubber seperate and pull out from between the two which caused the outside hub to rotate. so the when the guy said the HB slipped, it is very possible.

 

[HISSIN50]

yes it can in it's own way. there is a pressed on part that has rubber between it and the hub. I had a problem with getting my car timed after I worked on it and also had a bad vibration. the outside hub with the timming marks can slip causing problems. it's not a common thing but it does happen. I had a guy who races in fun ford weekend modular maddness class fix mine. he showed me the balancer and it was a two seperate parts: the part that bolts to the crankshaft and a pressed on outside hub which does the balancing and used for timming. mine had the rubber seperate and pull out from between the two which caused the outside hub to rotate. so the when the guy said the HB slipped, it is very possible.

absolutely correct (i was waitin for someone to say something). as said, there is an elastomer between the inner and outer ring. the timing marks are on the outer ring. often amongst other reasons (cracked elastomer, outer ring run-out, etc), a car that goes to get timed and the timing marks are AWOL suggests a slipped balancer.