pinging after plug change

[SeanD1111]

Title says it all!

J/K

About 3 weeks ago I changed the plugs in the car (2001 GT). I used autolite copper 764's, and gapped all of them to .054. It seems that right after I made the change the car started to ping. What could be causing this?

The car: 2001 GT, K&N, O/R H, cat back. (Pretty stock) (60K)

I went to 93 octane, but it did not help. have not been "on it" since then. The weather has been getting cooler here also, not sure if that matters. It also seems I have been getting more valve train noise since the plug change. Oh I also at the same time went from a synthetinc blend 5-20 to M1 5-30, not sure if that might be it also.

Thats all that was done at the time.

 

[CanadaStang]

Ah, nope not the oil. Check and see if you pulled a vacuum line off when you were changing the plugs. Also check to make sure you have no leaks between the maf and where the intake tube fastens on at the engine.

 

[Go HoTO!]

Man, that's a tough one. The colder weather should help prevent pinging if anything. Those plugs should help your spark, not hurt it.

While this sucks, I would put the stock plugs back in and see if the problem goes away. If it does not then it's not the plugs. If the plugs are the problem, I can think of no reason why this would be the case. The next thing I would do then would be to close the gap on the plugs. Actually, your problem might be that they are gapped too big. R U sure you gapped them correctly?

 

[SeanD1111]

Ah, nope not the oil. Check and see if you pulled a vacuum line off when you were changing the plugs. Also check to make sure you have no leaks between the maf and where the intake tube fastens on at the engine.

Checked, double Checked, and checked once more, no leaks.

Not sure, but drove the car yesterday to get gas (put 89 in it) and am driving it today with no pinging. The valvetrain is quit again and there is no pings under load. Maybe a bad tank of gas? The weather has warmed back up also, so not sure if that has anything to do with it.

It was strange to say the least.

I thought it might have been the plugs, but I removed them all and checked the gap on each, all were fine. The original plugs are long gone, and it had autolite 764's in it before this.

I have always thought / wondered if the vehicles computer advances the timing in the winter to heat the car to operating temps faster. This would obviously cause pinging.

Do not know, but all seems good right now. It is suppossed to get real cold here over X-mas (at least for south Texas 20*) and if it starts to ping again, I may swap these plugs for 103's (one step cooler) and see what happens then.

 

[CanadaStang]

Yip, crappy fuel will cause you grief.
Colder air will help reduce pinging by cooling down the combustion chamber, reducing the chances of preignition. Warm air will contribute to higher combustion temp. So it's not b/c it's getting colder.

 

[Blown2002GT]

You need to get rid of those crappy autolites and get a set of NGK's......

 

[twogts4us]

You need to get rid of those crappy autolites and get a set of NGK's......

Gimme a break! What the hell is wrong with Autolites?

 

[Go HoTO!]

Gimme a break! What the hell is wrong with Autolites?

Nothing! Lot's of guys use them!

 

[Go HoTO!]

Checked, double Checked, and checked once more, no leaks.

Not sure, but drove the car yesterday to get gas (put 89 in it) and am driving it today with no pinging. The valvetrain is quit again and there is no pings under load. Maybe a bad tank of gas? The weather has warmed back up also, so not sure if that has anything to do with it.

It was strange to say the least.

I thought it might have been the plugs, but I removed them all and checked the gap on each, all were fine. The original plugs are long gone, and it had autolite 764's in it before this.

I have always thought / wondered if the vehicles computer advances the timing in the winter to heat the car to operating temps faster. This would obviously cause pinging.

Do not know, but all seems good right now. It is suppossed to get real cold here over X-mas (at least for south Texas 20*) and if it starts to ping again, I may swap these plugs for 103's (one step cooler) and see what happens then.

There are different fuel curves for when the car is cold, but as soon as it warms up, there is no difference.