Need more code help..

[YouGotSpooled]

Well the first code Im kinda stumped on is code 42. I didnt really find much when I did the search.. Most of it was for auto trannys. Anyways, I removed the Speed Control Acutator. Drove it for a bit, then checked the codes.. had code 42, 51 and 52. So I put the SCA back on to the car, hooked up the plug and put the vaccumm line back on. I went over my knock sensor re-wire to make sure everything was good.. I had no continuity between the shield wire and the main wire. All the soldering was good.

I drove the car again.. And got the CEL light again (god damnit..) and pulled my codes. 42, 51 and 52 again. Sigh.. Anyways, Im just wondering why im still getting this code 42 after I put it back on. Its a 87 turbo 5spd.

Also is it possible that a knock sensor works only some of the time, making it throw a code now and again even tho the wiring is good? If I rev the car over 3000rpm, I cant get the code. But usually if I go driving for a couple hours and drive it a bit hard now and again, I get the code.

Im really getting sick of this CEL..

 

[3p141592654]

Does your speedo work? If the cable is broken it will set 42.

When you say "Speed Control Actuator" I hope you are not referring to the cruise control servo. That has nothing to do with code 42.

The speed sensor that sets 42 is under the dash driven off the speedo cable. There are no vacuum lines to it, so that's why I am wondering what you are describing!

 

[YouGotSpooled]

Well it says "speed control acutator" right on it. Im talking about the piece in the engine bay. Also, my speedo did stop working. Im not sure wich part of it tho. The part that goes into the cluster doesnt turn. I guess maybe I just checked the codes after I took that out and assumed it was because of that.. My bad.

 

[YouGotSpooled]

ANyone?

 

[3p141592654]

Anyone what?

 

[jetjock]

^ lol. Man, I wish I had your patience

 

[YouGotSpooled]

About the code 52. Can a knock sensor work some of the time? Or does it either work, or not work?

 

[jdub]

Starting to sound like a broken record:

The knock sensor does "listen" for a 7 kHz frequency...this is the frequency that is produced when the engine experiences knock. However, this is not what produces a code 52. This code indicates a problem with the knock sensor circuit (open or short), the knock sensor itself, or the ECU.

When the ECU gets the signal that knock is occurring in one or more cylinders, it will retard timing. It bases the amount of retard on if the knock signal is "strong", "weak", or in between...basically it steps the amount of retard. When the knocking stops, the ECU restores timing advance a little at a time in fixed degrees.

When you have a code 52, the fail-safe function of the ECU sets ignition timing at a fixed retard angle (no more than 10 degrees iirc). This will definitely affect engine performance.

You could always try to do a search....:3d_frown:

 

[YouGotSpooled]

I did. But I never found anything about if they could work some of the time. Also, the stuff I found on code 42 was about auto trannys.. So I thought id put it all in one post.

Sorry. :nono: