5.3l Engine Clatter
TECH Addict
Joined: Aug 2005
Posts: 2,305
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From: Monroe,NY
Make sure all your coils are good. A bad coil can cause your problem. I has one that was weak that acted similar to yours. I have headers and checked the temp of each exhaust primary and found one a lot cooler than the rest. That was my bad coil.
Thread Starter
Registered User
Joined: Jan 2014
Posts: 12
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From: N. Richland Hills, TX
Wouldn't a bad coil cause it to misfire and throw a trouble code? Also, I guess the only way to test a coil is to measure the primary and secondary resistance and compare all eight to each other, correct?
Thread Starter
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Joined: Jan 2014
Posts: 12
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From: N. Richland Hills, TX
Ok, I've check my coils and wires and found no issue and no difference between them. I'm also running new ACDelco plugs at .40 per the dealer. Also, as a test to verify if the catalytic converters were causing the issue I removed them and placed a temporary straight pipe in their place. No change, I'm still getting a lot of detonation clatter. I've noticed while logging the sensor data that the spark timing drop everytime I open the throttle whether it clatters or not, if it's cold or hot, no matter what gear I'm in. Is this normal for timing to drop while trying to accelerate? I have graphs showing this if anyone is interested.
We had a customer with pretty much the same problem as you. Told him to replace the knock sensors and harness. He did but with the Autozone brand. Still had the problem. We swapped out the knock sensors and harness with some new GM ones, problem solved. His truck was an 01. You can see its pulling timing, so that is where I would start.
Thread Starter
Registered User
Joined: Jan 2014
Posts: 12
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From: N. Richland Hills, TX
This did all start with a bad knock sensor and I did replace it with either a Autozone or Oreilly brand. I think it was a Borg Warner. I was thinking the MAP sensor may be out of spec and causing the ECU to not recognize what the TPS is doing.
Guess I could change both knock sensors and the harness and see what happens.
I'll keep you all posted. Thanks
Guess I could change both knock sensors and the harness and see what happens.
I'll keep you all posted. Thanks
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Joined: Feb 2019
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Knock sensors I also had had to replace knock sensors and after reading man forums, I learned that any brand other than AC Delco might work for a very short time, but would end up giving you problems again. When doing knock sensors GM sensors are the only ones compstable. On the question of TIMING, a worn chain and prob sprockets to, can cause your timing to be off from about 3 - 6 degrees. This will cause a rougher idle, possible loss of power, loss of gas mileage, and the clatter noise you refer to. Mine started the noise recently when at operating temp, but quiet when cold. I am thinking that is because of expansion and contraction, everything is a little tighter when it’s cold. I haven’t had much loss of power but I am down to 11mpg avg which is quite a bit low. But if u decide to tackle that job, it would be smart to also do oil pump, pick up tube, and screen while your at it. Since it is all right there and you wouldn’t want to tear all that down again later on. Water pump to if u haven’t already. Water pump gaskets at the least.
This did all start with a bad knock sensor and I did replace it with either a Autozone or Oreilly brand. I think it was a Borg Warner. I was thinking the MAP sensor may be out of spec and causing the ECU to not recognize what the TPS is doing.
Guess I could change both knock sensors and the harness and see what happens.
I'll keep you all posted. Thanks
Guess I could change both knock sensors and the harness and see what happens.
I'll keep you all posted. Thanks
