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edit: actually is/was code 22 ( Knock sensor)

Got code 12 (Abnormal signal emitted from starter switch) tonight. Found very few posts on here about troubleshooting steps and solutions for it. About to go out and reset the ECU and drive home. I guess this would make sense why yesterday morning, the car struggled to start, but eventually fired up. Yet, no CEL was thrown until today (at least 6 starts later).

Any suggestions?

After making the post, I went back to the car, double-checked the codes and I copied it down wrong. It was code 22 afterall, doh.

Plugged in the green and black connectors and drove until the check engine light flashed to the ECU codes were cleared. Immediately after disconnecting the connectors and turning the car on, the CEL was back. I drove for 15 seconds, then the CEL light went away and didn't come back the whole drive home -- which also included several WOT romps.

While in the dark parking lot, I noticed it appears the top of the knock sensor has a crack down the top of the black plastic. I assume this is the sign a new one is needed? Also, today it was the first rain in months, and I noticed the knock/crank/cam senor connectors looked a little wet -- possible cause of the issue?

Anyways, if it IS the knock sensor which is going bad, why haven't I gotten a CEL until today and why did it go away after driving a short distance? hmm, I guess the knock sensor could explain why my AFR has been getting richer lately during WOT.... instead of the targeted 11.5, it's getting back down to 9.5.

Yes.replace the knock sensor.Done.

If there's a small crack on the outside of the knock sensor, there's no tellin' what's going on inside of the knock sensor.

I'm with gijonas.

just finished hyaving the same problem.

http://bbs.legacycentral.org/viewtopic.php?t=40534

want my knock sensor its the newer design only a year old no cracks i thought mine was bad turns out it was my coil pack ... Just wasted 80 on a new sensor ill sell you my old one for 35 shipped if you want.

Some posts have stated the knock sensor must be oriented a certain direction. Any justification to this?

I just made sure that mine sat flush with the mounting point. So either it doesn't matter or I lucked out and positioned it correctly. I'm more inclined to lean towards the former.

i think it's just for the wire. i think it gets pointed towards the rear passenger side.

things are a little tight in there.

Decided to install the KS in the same orientation as the original -- and yes, it was the ORIGINAL KS (grey) one too. Was cracked on the top and sides.





There was a bunch of electrical tape on the side which was covering up this lovely crack:


Decided that since I had a new one, time to find out what the knock sensor was made out of and cracked it open.












Haven't had time to really drive it yet to see how much of an improvement it's made...

Ha, you really are an inquisative bugger aren't you? Well done.

i think youll be very pleased when you get on that throttle again.

Yeah...faulty knock sensor pulls a bunch of timing = no power and high EGTs

RJ93SS wrote:i think youll be very pleased when you get on that throttle again.

Indeed. Already a noticeable improvement in throttle response within a few miles of the KS install. Also pretty sure the EGTs are getting up there since I'm getting a very distinct 'hot exhaust' smell after WOT romps as the ECU re-learns.