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false kr where is it comeing from



LOL at Nick.. you guys guess which one. :th_biggrin2:

On the sway, is the point in the center pointing down? If not.. flip the bar. Do you physically hear any odd/loud/unknown noises coming from the engine bay when driving or revving etc? There's very little the PCM is going to see as knock that isn't from a cylinder. Especially since it learns noise levels to base knock off of. Did Paul give you any more insight as to his thoughts on it? Maybe a chipped piston causing a hot spot etc?

One more thing. Hop under the car and look at your knock sensors. I've seen a few that got hit by something and the connector going into the sensor was not straight, the connector going into the sensor was broken where it meets the metal of the sensor. This can cause what you are experiencing w/o a doubt.
 
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It is completely stupid to think that its "hitting something" the same way every time all the time to create this event at a extremely wide and specific RPM and throttle position... You people have NEVER seen this before, nor have you tried to fix it yet you are telling me that I am wrong.

OP... If you want to try fixing it, you are going to have to dig into the ICM and possibly PCM for hardware/wiring failures. Technically the harmonic balancer, and or somewhat the cam sensor (remember the cam sensor is only a .5x sensor) is going to be where the source of these problems lie at... The plan of attack for the cars that I found with this problem involved a PCM swap, followed by an ICM swap, harmonic balancer swap and finally a few case learns. This problem seemed to only show up in 98+ cars when running really wierd camshaft timing or custom harmonic balancers. 96/97 cars would just have this happen randomly to stock cars even.. and was usually way worse of a problem.
 
well this puts me in a bit of a query, @darkhorizon do you know of any threads i can read that would

help me understand this a little more.
 
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BillBoost37 said:
LOL at Nick.. you guys guess which one. :th_biggrin2:

On the sway, is the point in the center pointing down? If not.. flip the bar. Do you physically hear any odd/loud/unknown noises coming from the engine bay when driving or revving etc? There's very little the PCM is going to see as knock that isn't from a cylinder. Especially since it learns noise levels to base knock off of. Did Paul give you any more insight as to his thoughts on it? Maybe a chipped piston causing a hot spot etc?

One more thing. Hop under the car and look at your knock sensors. I've seen a few that got hit by something and the connector going into the sensor was not straight, the connector going into the sensor was broken where it meets the metal of the sensor. This can cause what you are experiencing w/o a doubt.
Click to expand...

i will check this out, Pual didnt seem to know what was causeing it he said it could be

the exhaust but im pretty sure its not.
 
I've seen quite a few cars with exhaust hitting/huge leaks after the front O2 etc and no KR from either of these mechanical issues. If you read up in the GM manuals how KR is metered, read etc, you start to understand how tough it is for oddball little things to cause it. The pcm isn't just stabbing in the dark when it reads noise and filters it to be knock.
 
That's not new info. That's lack of boost which brings up compression and also raises cylinder temps.

It's kinda like saying, if you don't start the motor you don't see any kr. It's a given that you likely wouldn't have an issue without boost. Although that would point more toward real detonation.
 
i sorta had that feeling cause it revs so slow its like im less than half throttle, but does that rule anything out?
 


3.4" seems a smidge small for that, considering that equates to a 3.2"~ on a GenIII.

I also don't think rockers net that much of a gain...

I'd rather try a larger pulley and see if it helps.
 
I wonder if PRJ used 04+ timing tables on your BIN file... could be the source of your KR at low RPM/high load. IE: accelerating slowly up a hill on the highway.
With the new info I also think you didn't fully understand where I was going with the TCC locking.
 


it had the kr before i took it to prj, thats why i took it to him, also i need the pk3 crap taken out of my tune cause it was shutting off my fp.

can you elaborate on the tcc because i was very confused
 
blueguy said:
3.4" seems a smidge small for that, considering that equates to a 3.2"~ on a GenIII.

I also don't think rockers net that much of a gain...

I'd rather try a larger pulley and see if it helps.
Click to expand...

I have a 3.5 and told paul to put it on but he said it didnt need it
 
jrb1027 said:
it had the kr before i took it to prj, thats why i took it to him, also i need the pk3 crap taken out of my tune cause it was shutting off my fp.

can you elaborate on the tcc because i was very confused
Click to expand...

TCC is your torque converter clutch. When you're cruising, it locks up and gives you a better mechanical efficiency by providing the engine and transmission with a solid connection, rather than a fluid one.

It also places a higher load on the engine in certain circumstances.
With this new information, it sounds like your KR is from actual knock (part throttle knock) and you should not disable your Knock sensors as it could quickly lead to a blown engine.

At this point you really need someone else to check the tune/car over who is experienced and not in it to make money.
Even the best of the best can sometimes make mistakes, and even someone who's been doing this forever can ignore/dismiss things for various reasons.
 
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