I'm pretty sure I'm getting false knock

ssgtgoodwrench

New Member
So I am huge car guy that is new to the buick world but i think i am catching on. So i have a 85. Just performed a 86-87 ecu conversion. Got a TT chip for my set up, a LS1 Maf, Performed a tune up and installed a manual boost controller. I also delete the EGR and all the emissions crap. I have a nasty exhaust leak were the DP meats the Test pipe. Its pretty loud. So I do all this work and taker her out for a joy ride. I have a fresh tank of gas and i have the boost controller set to 12 psi. No matter what i am getting timing retard and the knock gauge is showing knock. Even at part throttle when i am only at 6psi it is retarding timing. The engine runs good. She does have a small ticking noise that i think is a shitty lifter on the Pax side. I am leaning towards false knock. I mean i dont see how the engine could knock on light throttle and minimal boost. Has anyone run into this before. I am going to fix my exhaust leak and the light ticking noise and see if this solves it. Do the 84-85 have knock sensors that are prone to going bad? Is this a common issue at all? Thanks for any help you can give guys. Really appreciate it.
 

BRAD_PADGETT

Well-Known Member
The change that your knock sensor is bad is virtually zero. The first step is to check the knock sensor for the correct torque. It should be 14lbs. If that is not your problem then your nightmare may be before you. The next step is to get a scan tool. I recommend a powerlogger. Then start tuning and learning. The powerlogger will allow people to help you diagnose the problems and keep you from throwing money and parts at the car out of desperation. This is based on my experience with my 85. I chased knock for years and only a powerlogger helped me find it. My case was a 140 block mated to my 2004r transmission. The knock gauge hit the lip of the transmission housing. I would see knock at a certain rpm and not under boost.
 
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