Getting weird random knock after tune
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From: Mt Morris, Michigan
Getting weird random knock after tune I have been tuning my car after installing some TFS215s & 42lb injectors. I feel I got the AFR dialed in pretty good by recurving the MAF table, at idle & WOT runs its 12.2-12.7 in OL. I did pull 1 deg timing from the upper RPM range(2-6000rpms) because of the higher CR. Heads were milled .010. I had it dynotuned last year after the cam install so it started up & ran very good after the new heads with the new IFR table for the 42s. So yesterday after doing a few runs & getting the AFR dialed in I put the PCM back into CL to see how it runs & I am getting some random spots of KR at cruise & part throttle & I am not sure why or how to get rid of it. The car runs & idles good, like before I did the heads but with more power of course. I do have a log to post up but cant figure out how to post it up. It is in CSV form.
May be false knock. Cut 10 deg from the entire timing table and take her for a spin. If you are still seeing occassional knock, then I would vote false knock.
If it goes away, then you may have to do some point reductions in your timing table (g/cyl vs rpm). Hotter ambient temperatures will make cars more prone to knocking.
If it goes away, then you may have to do some point reductions in your timing table (g/cyl vs rpm). Hotter ambient temperatures will make cars more prone to knocking.
Thread Starter
TECH Addict
iTrader: (11)
Joined: May 2008
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From: Mt Morris, Michigan
Here is the log with the knock. The only thing that I noticed about the scan is where I get the knock its a lil lean at cruise but under WOT its not lean at all.
Last edited by flintwrench69; Aug 22, 2010 at 08:51 PM.
