Knock Retard ???????
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Knock Retard ??????? My buddy Just installed a new cam and he's getting kr. Changed knock sensors and still getting it. No matter how much timing I pull with HP tuners it still has 4 degree's of knock!! Anybody have any Idea's??
It's actually my car. I really don't want to turn them off if I don't have to. I was wondering if anyone has had a problem like this with a timing tuner?? I am curious if this could have anything to do with it?? Thanks.
Let's get back to the basics.... are you sure the cam is installed correctly? If it's off a few degrees you could be getting piston to valve tapping which could be causing the knock. Do you have a dyno graph of where the kr is? Is it getting kr all the time or at a certain range?
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clutch in you can get a 0.x blip with a 5K rev
WOT you get 3.9* on areoforce, HPtuners 4.0* soild. Pulled commanded timming HPtuners, didn't change anything (just the lower ITA # with KR)
Headers look to be clear, and the Y pipe. The car never had a KR problem,before. Only change was a cam with spring, SLP oil pump, and a LS6 intake.
Could the dual vavlesprings (sorry I don't have the PN right now, 2stroke should) be causing it? Some weird harmonics?
I'm familer with some of the L36 (3800V6's) getting KR form the yellow LS6 springs, witch it s weird but simi common ocurence. I think it's faluse, we should see if any racegas changes it.
Cam timming should be fine.
WOT you get 3.9* on areoforce, HPtuners 4.0* soild. Pulled commanded timming HPtuners, didn't change anything (just the lower ITA # with KR)
Headers look to be clear, and the Y pipe. The car never had a KR problem,before. Only change was a cam with spring, SLP oil pump, and a LS6 intake.
Could the dual vavlesprings (sorry I don't have the PN right now, 2stroke should) be causing it? Some weird harmonics?
I'm familer with some of the L36 (3800V6's) getting KR form the yellow LS6 springs, witch it s weird but simi common ocurence. I think it's faluse, we should see if any racegas changes it.
Cam timming should be fine.
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Pretty much anytime you go WOT spikes 4* and dosn't go away. No recovery or anything. So set up fueling, AFR is good, it dailed in fine. We pulled timming stil had 4* figured it's flase. Start at the basics. Checked the knock sencors. The rear sencor was soaked in oil, front and some corrion. So hoped it was them. New set of GM's, installed at 15 ftlbs. A little rtv on the rubber seal covers. Put fresh plugs, fresh 94 oct. runs fine other wise..........
The car shouldn't get KR. With only 20* commanded timming still have a phantom 4*.
I think the next basic, would be add some sunco 100 unleaded.
The car shouldn't get KR. With only 20* commanded timming still have a phantom 4*.
I think the next basic, would be add some sunco 100 unleaded.
Last edited by studderin; Mar 28, 2006 at 02:03 AM.
The kr start's at 4000 rpm's (approx) at stay's at 3.9 until rev limiter. Pretty positive the cam is installed correctly. The motor is making power at the correct rpm. Going to bypass timing tuner next and see what happens. Doubt that's it but It's worth a try.
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You could always desensitize the sensors by wrapping the threads in teflon tape and undertorquing them. (But it would be safer to diagnose via high octane fuel!) I had a similar problem years ago, when even race gas didn't help. Turned out a couple of spark plugs were left loose from the factory. They turned into glow plugs under load and tuliped the intake valves...
98 Knock Sensors are overly sensitive. Upgrade to the later model knock sensors and harness and you wont have the problem. Only time it should get turned off is if its absolutely necessary. They will always read 4 degrees knock retard w/ cams especially. You can tune around it, or turn them off but i would say upgrade.
Originally Posted by 02WS6Bird
98 Knock Sensors are overly sensitive. Upgrade to the later model knock sensors and harness and you wont have the problem. Only time it should get turned off is if its absolutely necessary. They will always read 4 degrees knock retard w/ cams especially. You can tune around it, or turn them off but i would say upgrade.
The motor is a 99. The car and pcm are 98. I just put two brand new knock sensors in the car.
when i first bought my car(98) i had a 01 motor with the old 222 98 sensors i keep getting 4* or KR. i switched to the 603's and harness, and that got rid of the KR. do you have headers?