I have had this problem for a while with my 92 ssei.

With the car fully warmed up, driving at about a steady 40mph with the TC locked up, I get pinging when I lightly add some throttle. It'* only audible if I have the windows open and I can hear it reflecting from something nearby. If I force the TC off, no problem. I get no pinging on heavy throttle.

I always thought that the computer would retard the timing before I should hear anything. I don't have a setup to see if in fact I am getting KR or not. Is it possible that maybe the KR circuitry is not working? Maybe the ignition module is defective?

Mods: Hardly any. Using bosch platinum single electrode plugs. I replaced the knock sensor, no change. I'm using mobil 93.5.

Oh, I also ran through two bottles of techron, no change after that either.

There must be a solution to this.

Thanks

One thing, our cars HATE Bosch plugs and 02 sensors. Don't use either. Get new plugs and see what happens. And get an AC Delco o2 sensor if you don't already.

If you haven't got a code from the pinging, the knock sensor might be bad and the PCM doesn't know it.

I agree with the plugs. Get NGK or AC Delco, then check again. As far as the knock sensor is concerned, it'* impossible for the sensor or wiring to fail without setting a code 43. ABSOLUTELY impossible. It'* a check/balance or send/return system. Failsafe.

See, we have a checks and balances system, too. Thanks for setting me right, Bill.

I was just reading that section of the FSM a couple days ago for the two cars we have in 92-99 with code 43'*. The PCM sends out a DC signal to the sensor, and the sensor sends back an AC signal, variable by the amount of ping, back on the DC return.

If the PCM fails to send the DC to the sensor, it'* usually more serious, and the PCM will be obviously bad. If you have a code 43, it'* mostly caused by a bad wire, bad sensor, or grime/buildup on the sensor or the threads between it and the block.

In this case, no code 43, but there is pinging.......need to ignore the Knock Sensor circuit and find the root cause, and I REALLY like your idea of at least ruling out the Bosch plugs. That'* the necessary first step.

Before you do anything else, clean your mass airflow sensor. Remove the sensor and very carefully use a Q-tip and denatured alcohol to clean the wire elements. It'* easy, quick and cheap to do.

...very, very carefully...

I want to try different plugs but after reading lots of posts, I am still not sure what to get.

At first I wanted to get TR55IX plugs, but I would have to mail order them.

Then I was looking at AC 41-940, which is a premium double platinum, and I can get those for $6 each at AutoZone.

But in a lot of the posts I read that just a plain old copper plug (NGK TR55 or the plain delco) may be best for my supercharged engine. I am trying to figure out why. I read in one post that someone says the copper will melt under detonation and the spark will stop. Yes and monkeys will fly out of my butt !!!

The only possible explanation I can think of is that a regular copper plug might cool off quicker under a quick increase of boost, thereby reducing the chances of pinging. Whereas the little platinum or iridium tip might stay too hot and be a source for preignition. But this is only a theory of mine, I have no real info to back it up with.

So if anyone knows the real reason a plain old plug is better, please let me know.

BTW, I think you need to take all the spark plug hype with a grain of salt. Yes, the platinum and iridium tips last much longer. But what about the reduced firing voltage it requires? Does that really matter? My old 1972 chevy 327 with lousy points and a crappy coil ran just great. So does my three-coil super voltage system really need a plug that fires at a lower voltage?????

Thanks

go with the NGK V-Power TR55. It'* one heat range colder than stock. If you still have a problem, get back here as quick as possible so we can fix it before it ruins the plugs (they're inexpensive, so maybe buy 12).

And scan for codes again.

Ok guys wait till you hear this one.

I was changing my valve cover gaskets so I figured it was a good time to change out those Bosch platinum plugs. The cover gaskets were quite a project but that'* for a different post.

First, for those of you who don't know what a standard Bosch single electrode platinum plug looks like, it has a very tiny platinum tip and it is totally encircled with the center insulator. So all you see is the end of the tip that is flush with the top of the insulator. I have had great results with these plugs in other cars, and it'* a brilliant design.

My plugs have been in the engine a little over 1.5 years, so that'* maybe 25k miles for me. Three of the plugs looked normal. On one of them, the tiny platinum end was reduced in diameter more than half, so it looked like the end of a needle inside the insulator. And on the remaining two, the center tip was gone !!! There is just a little hole in the end of the insulator where the platinum used to be. I bent the ground electrode out of the way, and the center conductor is about .020 to .030 below the surface of the insulator. If I can get a picture of this I will post it later.

So NOW I see why you guys say not to use them with the SC. I wonder how this happens.

I replaced these with the NGK TR55 as instucted by many of you. It'* too early for me to tell if this has solved my pinging problem, I just finished it tonight. But I'm glad I got those Bosch out of there, my plug gaps were all over the place. It'* amazing what this ignition system will fire through.

I do have a tip. To remove the rear valve cover you have to remove the alternator brace and the engine lift bracket at the back of the head. Well once those two parts are out of the way the rear plugs are SO much easier to get at. From now on those parts come off before I even attempt the plugs. The most difficult part is usually getting the plug boots off, although the silicone grease I put on last time seemed to help.

Thanks for all the info .....