92 code 43 ESC
08-30-2017, 12:10 PM
#1
Race Director
Thread Starter
92 code 43 ESC
This code 43 just popped up. I understand it something to do with the knock sensors. Any ideas as to what should be done? Years ago I put in Crane roller rockers, but they seem very quiet. I still have the original knock sensors with almost 70 K on the Vette.
09-01-2017, 01:58 PM
#3
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09-01-2017, 02:47 PM
#4
Race Director
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I might be having an electrical problem as my radio quit and another code popped up (28).
Last edited by Strick; 09-01-2017 at 06:36 PM.
09-04-2017, 06:04 AM
#5
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20+ years ago I had a Code 43 in my 93 Blazer that had dual knock sensors. This is what I found:
Could be corrosion on the threads of one of the knock sensors is adding resistance, and the system fails the DTC43 diagnostic. Check the resistance of the center pin to the body of the sensor then again to the block. If you find one of the sensors is different (higher resistance to the block) clean that sensor's threads.
Could be corrosion on the threads of one of the knock sensors is adding resistance, and the system fails the DTC43 diagnostic. Check the resistance of the center pin to the body of the sensor then again to the block. If you find one of the sensors is different (higher resistance to the block) clean that sensor's threads.
09-17-2017, 08:20 AM
#7
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Here is what I did. First I followed the FSM and tested the lead coming from the ECM with the key on and got the required 5 volts on both leads. then I tested the resistance between the center of the knock sensor and ground, bingo, the driver's side was not within limits, 3300-4200. So, I had to look around for knock sensors and the dealer$hip was the only place that had them in stock. They were AC Delco and,yes, they had sealant on the threads. Both tested fine and I installed them. My anti freeze was clean and still nice and green, but I replaced it anyway. I really didn't have to replace both sensors but I figured if one failed then the other might be close behind. The results....drum roll, was successful and the code went away. As a side note, having the electric water pump makes it easy to burp all the air out of the system. 
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Red 91 (09-17-2017)
09-17-2017, 02:41 PM
#8
Race Director
Thread Starter
Glad you got it fixed. Coolness.
Did you happen to check the old sensors for continuity between the center pin and the body of the sensor? My money is on the sensor was still good, but the connection to the block (the threads) had become resistive. 3,500-4,500 ohms is a bad connection, not an open circuit.
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Did you happen to check the old sensors for continuity between the center pin and the body of the sensor? My money is on the sensor was still good, but the connection to the block (the threads) had become resistive. 3,500-4,500 ohms is a bad connection, not an open circuit.
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