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1992-1999 Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

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Old 11-03-2014, 08:23 PM   #11
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Hope the magnet didn't fall off the cam gear.
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Old 11-03-2014, 08:32 PM   #12
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Well, I managed to get the cam sensor out and it'* covered in junk. Grease and some coolant from the elbow letting go recently. Seems the o-ring wasn't sealing very well anymore. I cleaned out the hole where the sensor sits and I felt something in there that I assume is the cam magnet. Never really looked at one before. Nothing fell out of the hole and nothing was attached to the cam sensor when I removed it.
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Old 11-04-2014, 08:26 AM   #13
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codes gone? clean the plug?
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Old 11-04-2014, 08:55 AM   #14
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Cam magnet doesn't attach to the sensor, but the cam gear itself.
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Old 11-04-2014, 07:26 PM   #15
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Used my inspection mirror and turned the crank by hand and visually verified that the cam magnet is still on the gear. Cleaned it off as well. Installed new sensor, cleaned the plug, cleared codes with reader.

Fired up and let it run. CEL came back on so I scanned it while it was running. Same code for a failed cam sensor. I visually checked as much of the wire harness that I could all the way from the sensor to the ICM and all looks well. Is there a way to use a dmm on the plug to the sensor to figure out if the ECU is getting the signal? Starting to think bad ECU since I know this year is known for it.
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Old 11-04-2014, 08:49 PM   #16
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Just for giggles, check and make sure the ground wire is still attached to one of the ICM bracket bolts. It should be on the bolt circled in red tucked in on the backside of the bracket.

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Old 11-04-2014, 10:50 PM   #17
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Just took a look at the ground. It is right behind the bracket as it should be and the wire is tight.

I've also done the following:

Probed wire "J" at the ICM for Cam signal test- DMM shows 6.53V and then as the magnet passed by dropped to 00.02V.

Probed wire "N" from the ICM to test for power to the sensor. Shows 10.67V.

Probed wire "M" from the ICM to test for ground to the sensor. Showed 12.02V.

The wire letters are from a how-to I found online.
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Old 11-05-2014, 09:15 AM   #18
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The crankshaft sensor is also tied into 2 of the cam shaft wires. Possibly skewing your results.

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Old 11-05-2014, 09:32 AM   #19
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his reading sound good to the ICM. i would see if you have it out to the pcm. should be getting that same result on F, and looks like the black wire to connector c1 pin 5 on the pcm
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Old 11-05-2014, 09:35 PM   #20
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Thanks JW! I will check out from the ICM to the PCM. And great diagram Mike, I will add that to my collection for this car.
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