runn4

I have a 95 4runner with the 3.0. The check engine light was on and it was throwing the code 52, knock sensor/wire. I am in the process of taking the engine apart and noticed the the wire to the fuel injector of cylinder 1 was disconnected.. Could this cause the code 52 or should I continue the process? I am about half way done so I don't know if i should put everything back on and see if it was the fuel injector wire or I should just finish everything up..

Also there I have noticed some exposed wire on the knock sensor wire where at the end where it plugs into the wire harness..?

thanks

scope103

The knock sensor has nothing to do with the injector circuit, so I would be very VERY surprised if a disconnected injector is related to a code 52.

If you see exposed wire on the Knock sensor wire (or anywhere else), it means the wire is damaged. How bad? Hard to say. But the knock sensor wire is shielded, so if it is damaged it could take out the shield, and that will prevent the ECM from being able to pick up the sensor signal. Hence code 52.

SoCal4Running

Yes the knock sensor has nothing to do with the injectors BUT with the light on could it not be from detecting a vibration.

Could this not be from the engine skipping because of the dead cylinder?

shaeff

No, the knock sensor's circuit operates "invisibly" meaning that when it's working you won't really know it.

Read through here, starting at the very first page. It should answer some of your questions about the knock sensor circuit.

https://www.yotatech.com/forums/f116...thread-216933/

Read at least through post 20.

runn4

OK thank you for the clarification, that info helped a lot. Well i got the intake manifold off and the wire was in pretty bad shape, had a big break of exposed wire that was covered in a in layer of electrical tape. The knock sensor itself looked ok, I will test it later. There was also a lot of old oil underneath the intake manifold and oil was in the connector also, so that could also contribute to my problem.

Chip N Sawbones

I've been driving around for months with one of my fuel injector wires disconnected and never got a code 52. I always get and ignore codes 25 and 26 for the fuel mixture, but I was getting those before I disconnected the injector, as that cylinder doesn't have any compression.