anyone ever heard of a knock sensor not working at all? Is something like this possible? Just kinda curious cause Im new to the whole alky setup and so far Ive been able to get 22p.s.i with 91 and 20*23* turbo tweak chip and 0 knock. 02's are in the 780 range. I have a pt-54 on there right now and from what I understood in an earlier post you cant run that much boost with a larger turbo? Ive never had this car show any knock before on the scanmaster even before the alky and running straight 91 and 15p.s.i. so thats why I was curious.
knock sensor?
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GotGas8668
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- Apr 9, 2003
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it is completely pissoble that it is not detonating
changing them isnt all that fun not too hard just need a long extension the sensor is pretty much under neath the coil pack and ignition module but make sure you torque it correctly i think its like 16 foot pounds but double check first
over/under tightening the sensor could cause false knock or no knock detection
changing them isnt all that fun not too hard just need a long extension the sensor is pretty much under neath the coil pack and ignition module but make sure you torque it correctly i think its like 16 foot pounds but double check first
over/under tightening the sensor could cause false knock or no knock detection
Pull the plugs and look at them really really close. If you see any flea sized turds of silver or black on the center electrode, then you have detonation that's not being detected. If you see silver specs, that's AL off the piston, and black being carbon bits blow off the chamber/piston. If the plugs are old and you're not sure, put some new ones in, and 1-2 passes, if it's detonationing you'll see the specs.. But, the damage may already be done. You need to make the changes gradually, and check as you go.
Every car is a little different, just because someone else can do something doesn't mean everyone can.
yes the knock sensor CAN go bad...i found out the hard way when the boost was getting up to 22 psi on straight 93 octane for a while and i thought i wasn't knocking...but i could HEAR it...
also ended up blowing a headgasket last fall thanks to the alcohol injection system not firing fast enough when the boost was set at 25 psi...no knock sensor working = bam
replace it with a new gm unit...torque down to exact spec...
also ended up blowing a headgasket last fall thanks to the alcohol injection system not firing fast enough when the boost was set at 25 psi...no knock sensor working = bam
replace it with a new gm unit...torque down to exact spec...
strikeeagle
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- Jun 6, 2001
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- 3,326
14 foot-pounds.
Easily changed.
Requires removal of coil pack/ignition module/bracket.
Do not use teflon tape or other thread sealer - the sensor doesn't seal the cooling system or anything else.
Available from AC-Delco for less than 50 bucks...
Easily changed.
Requires removal of coil pack/ignition module/bracket.
Do not use teflon tape or other thread sealer - the sensor doesn't seal the cooling system or anything else.
Available from AC-Delco for less than 50 bucks...
You should be able to verify if the sensor is working by using a scantool that monitors knock...with car idling tap on the block back by the sensor with a ratchet handle or similar metal object...if it's working you'll see some knock..actually you may not even need the car running...not sure...
This is a good test. Trust me, if you don't get any visible knock doing this test, you've got problems! I had this happen, and the outcome was poor pin contact on the ESC module. I ran every step of the GM troubleshooting procedure (thinking yeah sure, bad pin contact!), but after pulling each pin, straightening it and re-inserting it, the circuit started working again. You'll need a Weatherpak pin tool, about $4.00 at NAPA.
