Spark knock, or NOT?
Thread Starter
Drifting
Joined: Oct 1999
Posts: 1,722
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From: Gloucester Va
Spark knock, or NOT?
I have my BLM's at or near 128 now for part throttle I'm now working on the spark knocks/timing. I think I am getting false readings what do you guys think? I'll show a spark knock @ say 50KPS/2000RPM/35*. But only one knock, and then no more even though I cheap the car at that range. I also show a few knocks @ 1300RPM with NO throttle/load, and only 23* timing advance. My BLM # for the no load knocks are at 124. So it's not lean. I also thought that with no load on the engine it wouldn't knock?
Burning Brakes
Joined: Mar 1999
Posts: 858
Likes: 5
From: Fl,USA
Re: Spark knock, or NOT? (88_vette)
If you want to know if they are real, disconnect the blk ground wire at the esc module on the pass side. I cut my wire and put a toggle switch so I could see. Just beware when it's off because the computer won't pull any timing out. You will hear the pinging if it's real. Mine does pick up some false knock from the headers and dual exhaust. It also did with gutted cats.
Oh another thing, there won't be a code unless you switch over when the car is running. Hope this helps.
John
Oh another thing, there won't be a code unless you switch over when the car is running. Hope this helps.
John
Thread Starter
Drifting
Joined: Oct 1999
Posts: 1,722
Likes: 0
From: Gloucester Va
Re: Spark knock, or NOT? (JOHN89)
Thanks for the input John. I can't doe the blk wire thing since I've gone to the 730 ECM. I do have headers, and such so I feel that may be a cause. I think it's res. from the exhaust, because it starts to get bad around 1300+.
since I can't due the blk wire I went ahead and pulled a few degrees timing out of the chip. I g uess we'll see if the knocks keep up. If so then I know it's false. Think it will work?
since I can't due the blk wire I went ahead and pulled a few degrees timing out of the chip. I g uess we'll see if the knocks keep up. If so then I know it's false. Think it will work?
Le Mans Master
Joined: Oct 1999
Posts: 9,713
Likes: 3
From: Sachse Texas
Cruise-In I Veteran
Cruise-In II Veteran
Re: Spark knock, or NOT? (88_vette)
I get a lot of false knock in my setup, in low and higher RPM's. I basically have it programmed out to where the max timing it can pull is 1 degree.
