OT: Need help with Barber's Buick (quad driver and cam sensor)

I'd send this to another group...but I don't know who is abominable and who is not (know what I mean?) I've followed and contributed to this group for
some time and would prefer to ask the question here. Thanks in advance.
Please forgive me for asking about a Buick....but I need help with my barber's Buick. I'm due for a haircut and this will be my third one without an answer on his trouble. Over the Christmas holidays he told me he was having trouble starting the engine cold. He had a buddy check it and found a bad camshaft sensor....so replaced. But it is still reporting 26 (quad-driver) and the 41 cam sensor. I cleared the codes, started the engine....and 26 and 41 returned. The engine runs good once started. It is a 91 Buick with 3.8 "C" engine. Do you think it is another bad cam sensor or does the quad-driver in the PCM bad? Any help would be appreciated. Below is a reminder of the code definitions.
26 Quad-Driver sense voltage shows a low voltage when battery voltage should be present, or if the sense voltage shows battery voltage when a low voltage should be present for at least 5 seconds when the engine was running.
41 Cam sensor signal was not received by PCM for the last 5 seconds while engine was running.
Skimmer
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Unfortunately a code 26 does not point to one single component as being bad, it is a sort of catch all code that flags an error condition for one of the numerous output drivers inside the ECM. All you can do is follow the code 26 flow chart and check each circuit as described in the flow chart.

VIN "C" 3.8, I'd be checking to see if the magnet fell out of the cam sprocket. Checking is easy, pull the cam sensor, hand crank the engine and look with a mirror until you either see the magnet or a hole where the magnet should be. If missing, you'll need to pull the front cover and cam sprocket, the magnet installs from the back side of the sprocket. :-( Bad design!
The two codes are probably not related.
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wrote:

Thanks Neil. I was thinking the quad driver sent power to the cam inductive pickup...but with a magnet, it might not be powered at all. I haven't studied it at all.
I don't want to start pulling parts so I'll pass on the suggestion about the magnets to him and let his buddy that replaced the cam sensor look at it. I don't know what to say about the quad driver. Could that be related to the transmission? He also has the transmission unplugged. He said it shifted jerky with it plugged in and ran fine unplugged. I know all this sounds crazy....but he is on a tight budget.
skimmer
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Hall Effect sensor. Yes, they're powered.

Odds are very good that the code 26 is because of the unplugged TCC.

Sounds like just another day in paradise.
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wrote:

Thanks again.
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NewsSkimmer wrote:

throwing parts at it and got those same codes. They wanted to replace the Computer and the EGR Valve, to the tune of about 600.00. Told em "Thanks, but no thanks". Found an obscure reference to a fuse panel behind the passenger side kick panel. Found a blown fuse there. Done. KenG
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Do you remember what fuse it was?
skimmer
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NewsSkimmer wrote:

KenG
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