What could cause knock retard without any knock? My scanner shows no knock but once in a while the car is still pulling timing. The connection to the KS is good and I'm NOT getting a code for KS low voltage.

 

How much timing is it pulling .6 2.0 is ok at wot , try changing gas... see what it does... mine pulls like 1.2 0.6 now that i have new opti and msd hooked up before with origional opti it never pulled timing, I guess now that it has more spark...it pulls some timing.

 

Its called false knock.It is a noise that sets off the sensor and pulls timing.This happens with a header change,RR change,exhaust leak,ect,ect.
The way to cure false knock is put the resistor inline to the computer and it tricks the computer into not hearing false knock.Do a board search.This also makes your knock sensor unworkable.
No an LT-4 KM won't cure it.

 

Are you saying the your scanner is showing values for knock retard, but the "knock count" is not incrementing?

 

I guess he is saying on the scan tool it shows some knock like on mine there is a knock retard value on the scanner 0.0 to whatever the car does at idle or wot or cruising, im thinking he is looking at the cruising. Probably picks up some false knock mine does 0.6 to 1.9 1.8 at wot.

 

Why don't you let ktg answer the question I asked?

 

No need to guess, he said "My scanner shows NO knock but once in a while the car is still pulling timing." That implies that he's attributing the change in timing to knock retard...but if there's no knock retard, then that's not it.

When does it happen? The timing is mapped within the computer...have you talked to the programmer?

 

That's right.

 

As I recall, I reviewed your scan logs, and you had NUMEROUS problems with erratic rpm readings, pulse widths suddenly dropping to "0", the fuel control system jumping to the wrong "cell" at WOT, 0xxmV O2 readings at WOT, knock retard that showed up at random, didn't decay, then suddenly dropped to "0" only to return in the next frame with a huge value. It seemed to me it was one of the most screwed up data logs I have ever seen. Did you make any progress toward eliminating the other problems?

 

Forgot to mention in the previous post.... knock retard is not always accompanied by an incrementing knock count. Can happen both ways. I just looked over a bunch of the logs I've got on file from people, and there are numerous cases of the PCM pulling timing, without seeing an increase in knock count.

 

Just curious, but how/why would you classify that as knock retard versus some other phenomena?

 

I've eliminated all knock counts by wrapping the KS threads with teflon tape and then doing a 50% desensitization using resistors. I now usually don't get any retard. That's helped a lot but it still has problems, mostly when the engine is warm. When starting the engine, sometimes it fires right off, the rest of the time it tries to fire right off but doesn't. I either then have to press the gas a little or crank for 8 or 10 seconds, then it will start. Then from a stop, I have to let out the clutch slowly while keeping the RPMs above about 1250 or I get a MAJOR hicup, sometimes the engine dies. Then once in a while at idle or at very slow speeds, the engine just dies for no apparent reason. It also bucks like a bucking bull in gear at idle. The only things I can think of is the cam is ground wrong by a bit (no, I didn't degree it) or the opti has an intermitant spazm.

 

Sorry i was trying to help he was not online and I was just trying to help?

 

I'm not sure I understand your question.

I made the observation that knock retard is not ALWAYS accompanied by incrementing knock count. I've also noticed that not ALL incrementing knock counts invoke retard.

 

After Injuneer's data log comment and this post, sounds like you have other issues to worry about. Have you tried another computer?