knock sensor confusion

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Sep 5, 2005 | 03:48 PM

sick-punk

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From: sidney ohio

knock sensor confusion

ok my vette throws a code 43 "knock sensor" when warmed up "closed loop". my question is it doesn't do it all the time but when it does it feels like i lose major power, does that mean its constantly retarding the timing or not working at all, and what would happen if i disconnect it?

Sep 5, 2005 | 04:17 PM

65Z01

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From: SE NY

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The ECM is doing it's job by pulling timing when it senses knock and protecting your engine. It checks it once after startup by advancing timing till it detects a knock count; if that test fails you will get a code 43.

What year is your Vette??

Sep 5, 2005 | 04:34 PM

sick-punk

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From: sidney ohio

86 tpi--- if it fails the test will it retard the timing as a safe gaurd, also it only threw the code when the engine warmed up.

Sep 5, 2005 | 04:43 PM

Morley

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From: GA

The ECM will run the self test several times during a drive. I had a code 43 that would set, then reset, then come back. It would do that about 3 or 4 times during a 20 minute drive.

Sep 5, 2005 | 05:37 PM

65Z01

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From: SE NY

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The problem can be in the knock sensor or with the ESC module, located to the right of the blower housing. There is an upgrade P/N on my site.

Sep 5, 2005 | 08:22 PM

CFI-EFI

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From: The Top of Utah

I think it matters quite a bit on the year of the car. In my car, "Code 43 means the ECM has seen low voltage at CKT 485, terminal "4" in white ECM connector, for longer than 4 seconds with the engine running."
"This voltage drops when the ESC module shuts off because it receives a knock signal."

Based on that, if the ESC is working properly and the knock stops within 4 seconds, the code won't appear.

RACE ON!!!