Bushwick Posted September 20, 2015 Share Posted September 20, 2015 Check engine came on either during, or immediately after jump starting my other car. Had it pulled and AZ stated P0325 which they were saying was possibly a knock sensor as that's what code is for other cars, but given it's a 95', that it might be something else. Car runs the same and always run premium in it, so it's not due to running 87 or something. I haven't tried resetting the code. Does the 95' EJ22 even have a knock sensor? If so, where is it? Is this common? What years/engine cross over with this knock sensor as a direct replacement? Could it be something else? Link to comment Share on other sites More sharing options...
Fairtax4me Posted September 20, 2015 Share Posted September 20, 2015 Yes it does. Look up my knock sensor 101 thread. Has all you need to know. Link to comment Share on other sites More sharing options...
Bushwick Posted September 20, 2015 Author Share Posted September 20, 2015 Thanks Fairtax. Sounds like it's bad then. Thanks for pointing out the 45 degree orientation as I'd never have known this. Are the Rockauto sensors holding up OK? That's where I get my harder to find parts from for my Saab and Subaru. Link to comment Share on other sites More sharing options...
Fairtax4me Posted September 20, 2015 Share Posted September 20, 2015 I've been running eBay made in China cheapies on both of mine with no problems. Unisia Jecs is OE brand. Rockauto has Bosch I think for a decent price that should work well if you're more comfortable with a name-brand. Link to comment Share on other sites More sharing options...
Bushwick Posted September 29, 2015 Author Share Posted September 29, 2015 (edited) Ended up with Auto Zone as they price matched and offered a limited life warranty, AND it's the Unisia brand. Anyways installed new and pulled battery cable to be safe and check engine light still on. Tried restarting numerous times, pulled cable again, etc. and still on. Does this take some driving to clear? Tried wiggling the wires and no change. Gonna run back to AZ and have the current code pulled just be sure it's not something else. Edited September 29, 2015 by Bushwick Link to comment Share on other sites More sharing options...
Bushwick Posted September 29, 2015 Author Share Posted September 29, 2015 Current code is also a P0325. I compared the new with old, and their numbers were different, but were otherwise identical. Also, the factory unit had no visible defects or cracking. Maybe an issue with the wiring instead? Are they known to corrode over time? When the factory knock sensor was still in, it cleared a couple times, briefly. Any thoughts? Link to comment Share on other sites More sharing options...
Fairtax4me Posted September 30, 2015 Share Posted September 30, 2015 Is the pad on the block for the sensor clean? Any corrosion there will prevent the sensor from grounding properly. Make sure the wire terminal didn't back out of the connector. The wiring for the knock sensor runs through the same connectors on the bellhousing as everything else. Unplug those and make sure none of the pins are corroded or dirty. Link to comment Share on other sites More sharing options...
Bushwick Posted September 30, 2015 Author Share Posted September 30, 2015 Is the pad on the block for the sensor clean? Any corrosion there will prevent the sensor from grounding properly. Make sure the wire terminal didn't back out of the connector. The wiring for the knock sensor runs through the same connectors on the bellhousing as everything else. Unplug those and make sure none of the pins are corroded or dirty. -The immediate area of where the old sensor sat was clean, but there was a lip on the outer edge of that. Suppose it's possible it could be on that lip. It was raining today and had to drape a giant tarp over the engine area with hood up to keep from getting soaked, so cleaning with power tools was out of the question. -The connector clicked into place and was very snug. Double-checked it twice so don't think that's it. -Can you be more specific on where they pass through and need inspected? Is it engine-side or under the dash? Is the connector clustered together with other wires? Or does it remain on it's own? The singular wire goes right into a protector case after it exits the bellhousing clip, so it'll be difficult for me to trace it otherwise w/o tearing into that protective sleeve. Link to comment Share on other sites More sharing options...
Fairtax4me Posted September 30, 2015 Share Posted September 30, 2015 Runs under the manifold over to the main engine connectors on top right corner of the bellhousing. I don't remember exactly which connector it is. Check voltage reaching the sensor by back-probing the connector. Should read something like 2.5V at the sensor plug with engine running. Link to comment Share on other sites More sharing options...
Bushwick Posted September 30, 2015 Author Share Posted September 30, 2015 Runs under the manifold over to the main engine connectors on top right corner of the bellhousing. I don't remember exactly which connector it is. Check voltage reaching the sensor by back-probing the connector. Should read something like 2.5V at the sensor plug with engine running. Thank you for the tips Fairtax. I'll try and get a volt reading at the connector tomorrow and go from there. The ABS sensors in the rear don't happen to run along the same area, do they? I've had a sensor issue I've been putting off (I can sometimes hear the ABS unit kicking in on first braking after starting the engine and moving along with the pedal pulsing and noticed the ABS light went out after installing the knock sensor- not sure if it's coincidence or not) Link to comment Share on other sites More sharing options...
idosubaru Posted September 30, 2015 Share Posted September 30, 2015 Check continuity from ECU pinout to knock sensor connector - that should be easy to find via wiring harness diagram. Or engine connector. Pin access via three connectors: ECU - Passengers Side Main Engine Connector - Knock Sensor Different dedicated wiring and areas - doubtful the ABS is related. Link to comment Share on other sites More sharing options...
Bushwick Posted September 30, 2015 Author Share Posted September 30, 2015 Thanks Gary. Hopefully it has voltage and just isn't seated correctly. This is the first real issue with the engine since owning. Just hoping the old sensor not being physically damaged i.e. the tell-tale cracking that it's NOT wiring related Link to comment Share on other sites More sharing options...
idosubaru Posted September 30, 2015 Share Posted September 30, 2015 it runs fine? average gas mileage? does it run identical even after the sensor change? i have seen failed knock sensors without the typical crack at the base. Link to comment Share on other sites More sharing options...
Bushwick Posted September 30, 2015 Author Share Posted September 30, 2015 (edited) Yeah, it runs great. Idles great too. It has a cold start slap/knock sound that goes away after warmed up, but it's had that since I got it. I'm not entirely sure it's engine related, though it does sound deep towards the back of the engine. Could possibly be something external as it doesn't increase with frequency or sound with engine revs. MPG is too soon to say as it was only driven about 8 miles since sensor went in. Just did an oil change the day before, so that made a difference in and of itself. The code seems to be a hard code as it was immediately lit after the battery disconnect, so I'm curious to see if there's a break in the wiring somewhere. Will update tomorrow afternoon with the voltage readings, if it has any. Edited September 30, 2015 by Bushwick Link to comment Share on other sites More sharing options...
Bushwick Posted September 30, 2015 Author Share Posted September 30, 2015 (edited) Probed and it was getting voltage. Pulled back out and noticed some grease or something had somehow gotten between the surfaces. Wiped it down again, then took a long chisel and knocked the outer lip off the block. Left the battery disconnected for 20 minutes and reconnected. It fired up and light finally went out. So it appears it's sensitive to the mating surface. Inspected old sensor and discovered it had a break internally near where the wire enters the sensor. It'd show readings if you moved the wire around. Having that sharp bend upwards with the wire to avoid hitting the bellhousing seems to be why. For future references to others stumbling on this, the signal wire was around 4.8v with the sensor disconnected and key on. With sensor connected and grounded through the center bolt, that voltage drops to around 2.3v with either key on or running. Sensor should be reading around 0.553 m ohms +/- resistance. So if you suspect your sensor is bad, check the resistance first with it unplugged. If you see an open circuit, it's bad. If it's still showing a value, try moving the wire around and see if it drops out. Hope it helps. Edited September 30, 2015 by Bushwick Link to comment Share on other sites More sharing options...
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