Code 52 still after changing both KS's????
 

Hi all,

Noob here and sorry if this is a dumb question. I've searched for KS related stuff and read a lot of info. But I'm still a bit lost.

I'm working on my moms 87turbo/auto. The dealership said it needed KS's so she ordered 2 of them. I just got done installing them and its still throwing code 52. I had the pos bat cable off and the EFI fuse out while I installed the new parts. When I finished up, started it and its still running like crap and throwing code 52.

Any ideas for me???

Thanks in advance!

Brandon

i think when you put a new KS in you have to reset the computer...

what is a ks?

KS= Knock Sensor

Alot of times, the code 52 is from the KS wiring, and not from the KS itself. Usually rewiring the 2 KS on a Turbo Supra (or 1 on a N/A) will correct the problem. Here is the step-by-step rewire page, and here is a thread in this forum discussing the rewire.

And make sure you have that negative battery cable disconnected or you pull the 15 amp EFI fuse out for a few minutes to erase the code from the computer.

I was under the impression that pulling the EFI fuse did reset it? The engine light was out for a few minutes and then came back on.


KS= Knock sensor

Pulling the EFI fuse cuts the power to the computer, and after a few minutes the computer no longer has a residual charge, thus clearing its memory of stored codes.

Thanks for the response!

What goes wrong with the factory wiring that we need to rewire the KS?

Well, it's a 87. So all the wiring on the car is about 23 years old.... After countless hot/cold cycles, the wires become brittle, insulation wears away.... The time is just rough for wiring, so it needs to get replaced.

Ok, I have now rewired the KS's. It sounded better on start up with a bit of a miss at idle. I let it warm up to opperating temp, hit the gas a few times and no CEL! I'm thinking I'm golden.....take it for a quick drive and it feels like its running on 2 cyl. but still no CEL.

Are the plugs shot after after it got driven in limp mode for 40 miles from my folks house to mine?

I'm done for tonight just looking for advice on where to start on it tomorrow.

Thanks once again!

I'd probably start checking your plugs, wires, and timing (in that order) next. It's possible that your plugs could have been fouled, and the ECU running rich while in limp mode might have fouled them more. Also these cars are notorious for leaking oil into the plug valley, so you may have oil soaked plugs/wires.

When you check your timing, be sure to check your valve timing before you check your ignition timing.