False knock...now what?
#1
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Ok for the past few weeks ive started logging autotap and noticed some minor knock retard readings, no audible knock though. So last night i put in 5 gallons of 100 octane mixed with about a gallon of left over 93 that was in my tank so i had about a 98 octane mix in there and still go the same readings...bottom line is it appears as if its false knock which is good and bad...good in the fact that i shouldnt worry to much about my engine blowing up but bad in the fact that the computer is taking out a ton of timing and robbing me of some hp...so what should i do now? Obviously there are a million things it could be is there anything i should do about it at this point or caulk it up to gm and forget about it?
Thanks
Bill
Thanks
Bill
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If this is a '98, many of those has knock sensors
that were too sensitive or sump'n like that, the
sensor was replaced with a new P/N in later models
and this might be worth looking into. Also check
for any sensor codes, water & spooge sitting on
them (like from hosing down the engine to clean
it) can mess them up & need them replaced.
Then there are the "usual suspects" for mechanical
false knock like exhaust banging, bad pulleys, and
valvetrain clatter. Might put a stethoscope to the
valve covers & see if it's a sewing machine or a
blacksmith shop in there. Things like bad rockers
and bent pushrods can make knock sensors trigger.
that were too sensitive or sump'n like that, the
sensor was replaced with a new P/N in later models
and this might be worth looking into. Also check
for any sensor codes, water & spooge sitting on
them (like from hosing down the engine to clean
it) can mess them up & need them replaced.
Then there are the "usual suspects" for mechanical
false knock like exhaust banging, bad pulleys, and
valvetrain clatter. Might put a stethoscope to the
valve covers & see if it's a sewing machine or a
blacksmith shop in there. Things like bad rockers
and bent pushrods can make knock sensors trigger.
#6
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sorry i didnt have a sig..it is a 98 and i did clean the engine bay when i first got the car but didnt take any autotap readings till recently...also i looked but there is no blacksmith in there??? Though there was a little green man so go figure
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#8
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HOLY CRAP old thread! I think it's safe to say Bill has learned a bit more about tuning since then and likely has this under control
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Originally Posted by Matt @ SDPC
HOLY CRAP old thread! I think it's safe to say Bill has learned a bit more about tuning since then and likely has this under control ![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
WOW, I did a search & thought I was back in the normal forum.
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