ECM code 43 = Knock sensor?
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From: Florida
ECM code 43 = Knock sensor?
I have a '86 with just under 6k miles now, not a typo 6k miles.....really. I received a "service engine soon" light today and checked for a code. The code I have is #43 and the possible failure is "Check ECM wiring. Replace knock sensor". First is where to go to check the ECM wiring and second is what is a knock sensor, where is it located, what does it do? Thanks in advance for your help. 
Thread Starter
Instructor
Joined: Aug 2004
Posts: 179
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From: Florida
I don't have a Helms manual......yet. I know the code and what its for I just did'nt have a clue what a " knock sensor " was. I know what it is and where its located. Sould I just reset the code or replace the sensor. A couple of part stores told me to reset first because MOST 99.99% "knock sensor" replacements are due to changing the starter out and breaking the sensor. I think I'll just reset it and see what happens.
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Once you locate the sensor, inspect it. Sometimes they get dirty with grease or oil and that will cause Code 43 on your DIC, especially after start up.
I think the L-98 only has one knock sensor. I believe it's located on the passenger's side under the vehicle near your starter motor. Look for a round object with an electrical connector coming out of it.
It sort of resembles those Walkman style headphones from the 1980's.
I think the L-98 only has one knock sensor. I believe it's located on the passenger's side under the vehicle near your starter motor. Look for a round object with an electrical connector coming out of it.
It sort of resembles those Walkman style headphones from the 1980's.
Last edited by onedef92; Aug 27, 2004 at 03:02 PM.
Drifting
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From: Charlestown IN
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If it's like my '85, the sensor is on the passenger side, just forward of the starter. It has 1 wire going to it. It's round and goldish colored. The ESC module for it is on the passenger side next to the heater blower facing out to the side. To test it, take something like a tire iron or I used a 24" long 1/2" drive extension bar. Start the engine. Go around to the passenger side, hood up, and hold the tool about 4" above the exhaust manifold and let it drop. When it "knocks" on the engine, the sensor should detect this and you'll hear the idle drop while it retards the timing. Neat trick. After resetting your ECM, if throws a code again, check the ground to the ESC module. Let us know what happens. 
