Code 43
Thread Starter
4th Gear
Joined: Apr 2024
Posts: 4
Likes: 0
Code 43
Hey all! I have a 1985. So as you can see from the title I got a code 43. Great 
I went in and replaced the knock sensor. Pain in the *** location. I reset the ecm. Drove to work no check engine. Coming back it popped back up about half to home. Now I did notice that I when I took out the knock sensor no coolant came out. Could the clog cause the code 43? I read the manual. Little confused on the b7 and all the instructions. Thanks in advance!
I went in and replaced the knock sensor. Pain in the *** location. I reset the ecm. Drove to work no check engine. Coming back it popped back up about half to home. Now I did notice that I when I took out the knock sensor no coolant came out. Could the clog cause the code 43? I read the manual. Little confused on the b7 and all the instructions. Thanks in advance!
Instructor
Joined: Dec 2016
Posts: 241
Likes: 77
From: Arlington VA
I chased this around for months on my 86. I know the 85s are sort of unique in some ways but I think the ESC system is the same. The system consists of the knock sensor, the ESC module and the ICM - any of those can get you a 43.
you didn’t get any coolant out of the block because there’s a build up of corrosion behind the sensor. You can clear it out with a screw driver and get ready for a shower. Maybe a good time for a flush?
I ended up replacing all three components and still had an intermittent code 43. Finally I found that the wiring harness from the distributor was flakey and since you can’t get them anymore, I made a new one. Problem finally solved. So I’d first check that all the connections are clean and making good contact especially the connector behind the distributor that goes to the main wiring harness. Best of luck!
you didn’t get any coolant out of the block because there’s a build up of corrosion behind the sensor. You can clear it out with a screw driver and get ready for a shower. Maybe a good time for a flush?
I ended up replacing all three components and still had an intermittent code 43. Finally I found that the wiring harness from the distributor was flakey and since you can’t get them anymore, I made a new one. Problem finally solved. So I’d first check that all the connections are clean and making good contact especially the connector behind the distributor that goes to the main wiring harness. Best of luck!
