Topic: knock CEL when EJ22 gets wet? wtf.

[darthekai]

OK, lots of rain here in calgary.. aand my CEL went off this morning when I started my car. Knock sensor voltage problem.
Had a KS CEL when I bought the car and I swapped it out for a new ebay one. A similar thing happened when I was running the engine in a car wash.
Just took freeSSM out on the road and saw some crazy itshay.

Knock correction stayed at -12 deg. whaat. I'm HOPING thats because the CEL is on and its in a bit of a safe mode.
Knock signal (on/off) was always off under load, but when my foot was off the pedal and I was decelerating or I was idling, it would flicker on/off pretty regularly..

A/F lambda went .8 - 1.75 (max value w/ stock sensor)

I have an exhaust leak somewhere, but only really shows up under high exhaust P and Q. This should mean I run rich when on the gas, should it not?

why would the thing run so lean? seems crazy.

also, I have a 2000 impreza OBS with an EJ222

[darthekai]

I just thought of something. Every once in a while when im parked uphill, the thing doesnt start properly, shakes a lot, and sounds like its running out of gas.

This suggests to me a busted-assay fuel pump. would this cause pressures at injectors to not be good enough and the car to run lean and knock on deceleration?

does anyone have a stock STi fuel pump for sale cheap?

[darthekai]

Well. I went through some motions and now im more confused.
I dug around and found some people who say the KS resistance should be <700k ohms (anyone know if this is true?)
checked the "new one" and it is just over (709k). ok... so I take my "broken" one and check it. 630k.
hmm..  reset ECU with "new" one. CEL comes right back on.
threw in "broken" one, reset ECU, CEL is off!!
ok. grab my laptop load up freeSSM.

knock correction is back at 0. Knock signal flickers On BRIEFLY then steady off.  Im like ok... good..

I go for a rip, making sure I hit 6k RPM and then dump throttle.
DOESNT flicker on/off during decel.
Rip around for a bit pushing engine hard. Min knock correction was -4 deg max was +7 (why would it advance it.. who knows)
Park back in garage. Signal flickers on/off at idle, steady off with any revs.
maybe heat has made the thing more resistive? turn engine off, quickly check ohms.. 545k

I have a new coilpack and wires sitting around, I think I will try doing that before spending $204 on a new bluestripe knock sensor from the part store.

I guess... I have a question for anyone reading this:
Have you ever hooked up freeSSM and watched knock signal (on/off) and seen it flicker at idle?? is this maybe normal?
what resistance is your knock sensor that works correctly?
is knock correction at -4 and +7 under high stress situations normal or is this something i should be worried about?

[darthekai]

Ill be over here talking to myself in the corner in the dark.. face lit only by the flickering screen of a laptop..

[seat safety switch]

Does your (new, I know) knock sensor look physically alright? The one I pulled off my '97 when I got it was cracked all the way down the exterior plastic housing and throwing enough spurious knock to kill a dog.

If you're getting the P0325 at startup chances are the knock sensor is broken and is failing the self-test. A replacement knock sensor from RockAuto was something like 30 bucks for me and worked a treat.

How firmly did you torque it down?

I wish I knew FreeSSM would work on my car when I was diagnosing my MAF issues.

[darthekai]

Haha no doubt. Its a pretty sweet little program I just wish it would log and graph. Um no neither has any signs of physical damage.. The one that shows too high a resistance is some cheap ebay one i found for $60 or something. Torqued both of them to 16ftlbs and made sure the angle was right.
Thirty bones is dirt cheap! Local part stores all want 200+

[AWDFTW]

Doesn't it only work for 1999 and newer though?