legacycentral bbs

ok so I have a check engine light and I am getting 21 nand 22 (Water temp and knock)
I replaced my water temp with a fairly new one that I had in my spare engine and I checked the knock sensor for continuity to ground per the chiltons. The knock sensor is not grounded and after replacing the temp sensor and resetting the ecu I STILL get a check engine light and the same two codes. WTF? any thoughts guys. The car runs but you can tell the ecu is retarding it like its on the short bus.

All I can say is check the harness in that area since those two sensors share the same area.

well I made it down the street this morning w/o a cel and I thought I was in the clear. I figured it was some moisture in something. so i get to the bottom and yup the cel comes on and the car is running retarded. Drove it work that way and when I got to work I called the local dealer which had a knock sensor for 71 and change. So at lunch I leave to go pick this thing up and no cel. keep driving and no cel. I finally say fuck that i'm turning around to go back to work and it comes on at the intersection lol. so I drive to the dealer and the cel is coming on and off a few times and I buy the damn thing. now I drive home tonight and no cel. Stayed off the whole time. I am going to hold on to the knock sensor anyway in case it comes up again I cam swap it but there must be water pooling somewhere in a plug. I'll keep you posted.

Check your grounds.
Specifically the one on the drivers rear of the intake mani. That one (along with others, I'm sure) can directly affect sensor signals to the ecu. Being as intermittent as you decribe makes it more likely a ground issue.

beatersubi wrote:Check your grounds.
Specifically the one on the drivers rear of the intake mani. That one (along with others, I'm sure) can directly affect sensor signals to the ecu. Being as intermittent as you decribe makes it more likely a ground issue.

Thks for the suggestion i'll look at that!