Knock sensor....
Thread Starter
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
Originally Posted by CFI-EFI
You are right. False counts will retard the timing when it shouldn't be, because there is no real knock. The false counts are interpreted as true knock and, as stated, would not trigger the check engine light or set a code. Oops!
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RACE ON!!!
I'm getting the code because one piece of the knock sensor setup is bad (either the ESC, knock sensor or wiring).
If I was getting knocking (false or real) it would retard the timing without setting the code, because that is how the system is supposed to operate.
I get a Check Engine light (usually during either WOT or 200 coolant temp like mentioned), and it feels as though my timing is being retarded when the code appears...
So if I have this right- I am getting a knock sensor code, and my timing is being retarded because (at least) one piece of my setup is faulty?
Team Owner
Joined: Dec 2000
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From: SE NY
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In your case it sounds like the ECM is testing the knock sensor circuit and getting a failure. So it sets the code 43 and goes into limp home mode where fuel is enriched and timing is set to some predetermined value.
Whereas, if the ECM detects knock counts (false or real) it will simply pull timing till the knock condition stops and then resume with usual timing control and no code is set.
In either case you will experience a loss of power when the event occurs. In the former case loss of power lasts until you turn off the engine and restart; in the latter case it only lasts until no more knock counts are registered.
Whereas, if the ECM detects knock counts (false or real) it will simply pull timing till the knock condition stops and then resume with usual timing control and no code is set.
In either case you will experience a loss of power when the event occurs. In the former case loss of power lasts until you turn off the engine and restart; in the latter case it only lasts until no more knock counts are registered.
Thread Starter
Melting Slicks
Joined: Jun 2004
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Thanks for all the help, very informative. 
I'm going to test out the ESC as 65Z01 suggested, my manual should take me through that step by step as well... I'll probably end up replacing the knock sensor, and getting an upgraded ESC as the tech tips mention... in any case when I get that far, I'll let you guys know the results....
I'm going to test out the ESC as 65Z01 suggested, my manual should take me through that step by step as well... I'll probably end up replacing the knock sensor, and getting an upgraded ESC as the tech tips mention... in any case when I get that far, I'll let you guys know the results....
Thread Starter
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
Got a new knock sensor, and a new electrical connector today...
put em both on. When I took the old connector off, I noticed the wire was bare... I kinda think that is what was causing my problems... but in any case: I put both of the new pieces on, and drove the car for about an hour. I did a few WOT runs, and I had no problems.
Code 43 fixed (knock on wood)
put em both on. When I took the old connector off, I noticed the wire was bare... I kinda think that is what was causing my problems... but in any case: I put both of the new pieces on, and drove the car for about an hour. I did a few WOT runs, and I had no problems.
Code 43 fixed
(knock on wood)
Thread Starter
Melting Slicks
Joined: Jun 2004
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Likes: 4
Originally Posted by redfast
Glad you fixed the problem.
What part af the wire was bad the connection or was the insulation stiped off the wire? Were did ya get the connector?
Thanks
What part af the wire was bad the connection or was the insulation stiped off the wire? Were did ya get the connector?
Thanks
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What year is your vehicle?
The ESC modules in some 87 thru 89's are suspect!
They pick up false knocks!
I believe NAPA ESC 312 cure the problem, there are Gm parts that will also do it, I think it is the ESC'sfrom around 88 Malibu's
Jack
The ESC modules in some 87 thru 89's are suspect!
They pick up false knocks!
I believe NAPA ESC 312 cure the problem, there are Gm parts that will also do it, I think it is the ESC'sfrom around 88 Malibu's
Jack
Thread Starter
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
Originally Posted by jackdaroofer
What year is your vehicle?
The ESC modules in some 87 thru 89's are suspect!
They pick up false knocks!
I believe NAPA ESC 312 cure the problem, there are Gm parts that will also do it, I think it is the ESC'sfrom around 88 Malibu's
Jack
The ESC modules in some 87 thru 89's are suspect!
They pick up false knocks!
I believe NAPA ESC 312 cure the problem, there are Gm parts that will also do it, I think it is the ESC'sfrom around 88 Malibu's
Jack
mine's an 85...
ESC modules from 85 to 89 pick up false knocks...
there is an upgraded one explained in tech tips...
that wasn't the problem...
the problem was that the knock sensor wasn't sending any data to the ESC... At least that's what I was told, and my solution tells me....
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