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trickster555
05-10-2016, 01:45 AM
I am learning how to use tunerproRT and data logging and as I am trying to understand everything I noticed that while logging and driving I get lots of knock counts while idling (550-600 rpm) but nowhere else and I make lots of WOT passes so I want to know if my sensor is going bad or the noise it hears is something else cuz my timing is set at a perfect 0 degrees with the connector unplugged (1989 v1500 fulsize blazer 5.7 tbi headers and intake only).
What could it be?

Mat

sturgillbd
05-10-2016, 01:51 AM
Is your exhaust touching the frame or a cross-member? Something loose or ratting on the engine? I wouldn't worry so much about knock counts at idle. If you aren't seeing any increasing counts under load, it is probably fine.
Look for loose hardware or something touching.
HTH
Brian

steveo
05-10-2016, 04:43 AM
knock counts at idle are no big deal, if your ecm allows you to specify knock retard per-range, just disable it for idle so it doesn't actually mess with your idle. my only worry would be if the knock retard recovers too slowly, it could propogate and kill your off-idle acceleration (for example you floor it from an idle, and it's nerfing timing advance for a period of time afterwards, you could cost yourself some power). if you can speed up knock retard recovery from off-idle, that'd be a good idea too.

89S10_Project
07-01-2016, 08:43 PM
-lightbulb goes off-

This may well be my issue. I have an exhaust pipe knocking against a crossmember, and a rough idle to the point it stalls at times after it gets to temp.