Help: GM 3800 engine ignition experts

Gentlemen,
REF: previous posts/threads were under the subject: "Help: where to buy GM style electrical connectors"
the car: 1994 Olds 88 Royale, 3800 engine, L27
Two scan codes are persistant/current:
1. P0321 - 18X Interrupts Lost 2. P0341 - Intermittent Cam Signal
I did the pertinent continuity/ohm tests on the wiring to cam and crank sensors, ICM, 8 way jumper harness, and PCM.
I tried a new crank position sensor: same codes. The cam position sensor was recently replaced by the owner.
I just performed the diagnostic procedure on the Spark Reference Circuit. The Spark Reference voltage at the PCM backplane, pin RB6, is 2.92V with engine running. GM Spec calls for 2.5V.
In a similar test, Fuel Control, pin RB8, is 2.45V. Spec calls for 2.5V. Seems ok here.
What do you think? Is the SWS/amp or Buffer/Amp in the ICM bad, requiring replacement of the ICM?
TIA Bill
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Bill,
You got a P0341 for an intermittent Cam signal. Why did you change the crank sensor? There was no reason for this.
I bet that if you changed the cam sensor, your problems would go away. If they don't, you might have a wiring or connector problem for the cam sensor.
Just because the cam sensor was previously replaced before, doesn't mean it's good. The pins on the connector could be broken, too. I have seen the female portion of the connector break off (meaning the little spring portion.).
Just a bit of input, GMdude
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just what should he do for the 321 ????

mean
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Bobo,
Um,... he did what he needed to do??? He found a sloppy connector pin at the PCM. It was one of my suggestions, that he check the connectors and wiring.
GMdude
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Um ......doesn't the cam sensor go into the ignition module, and not the pcm... so a loose connection at the pcm is nowhere near what you said to do.... I posted before he did so I was not aware he fixed it before I asked you about the other code... I still don't no why you were so worried about the cam sensor..even saying he was so wrong for tryin it. I was a litte more worried about the 18x Signal myself since you can't get a cam sync without it....

at
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Bobo and GMdude,
I missed some of your past posts because they did not line up under the original threads. I just now found them.
Yes, you told me to check the PCM connections. However, it was my bad because when I backprobed the PCM, I in fact caused the RB9 pin to make contact with the male PCM pin. Thats why I initially deduced that the square pulse wave was being delivered the the PCM. Later during a road test, I hit a bump and the MIL came back. Thats when I was convinced that it had to be a bad wire.
Yes, the cam signal does go to the ICM, but then comes back out, through the 8 way jumper harness, then on to the PCM.
Thanks for the help. Bill

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Bobo,
If he had found nothing wrong, my next suggestion would have been to check pins at the PCM. I have been there, and done that many times.
By the way,... Chief, it's not a 321, if you were talking about displacement? It has a displacement of 231 cu. in. The old 231's have long since disappeared, odd and even fire. This 3800 bares very little resemblance to those junk dinosaurs, physically, and in reliability.
GMdude
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you are a little to arrogrant for your own good.... try looking at his original post... I am talking about codes you moron... not a god damn engine... he had 2 codes to fix... not one ... next time read the entire post to make sure you don't look like a jack ass again.....now make sure you type something else to make your self look even more ignorant..... what are you a asep kid.....

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Crap, I was staring directly at the problem for over an hour. The RB9 female pin in the PCM connector was sloppy.
Many thanks to Bobo and the others that provided help along the way.

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