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I have the feeling my optical sensor in the opti is going bad, is there anyway to test it or do I have to basically swap for a known good unit? Here are my symptoms, tell me what you guys think...

'96 Impala with 180k or so... Delteq, Accel Opti, Tri-Y, RT Cats, PCMforless tune, Electric WP, Rammit Intake, mostly everything else is stock.

Seems to run fine until it gets up to operating temp, then it has random shutdowns, either at speed or idle. After about 10-15 mins, it starts and runs fine and the process repeats itself although at WOT it seems to be breaking up at the higher RPMs.

I can't remember how long that opti has been on there, a few years at least. I did notice a small oil leak that comes from somewhere on the front cover, I'm thinking the opti seal has gone bad and gummed up the optical sensor ? No CEL and there aren't any codes stored in the PCM. I've tested the coils as best I could and all the wiring associated to the ignition, all seems fine... Any input is greatly appreciated as the car is coming apart this weekend.
 

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Every optical sensor I have had go bad has set codes. Either or both of DTCs 16 and 36. One of the ones I have (currently for sale in an otherwise perfect distributor) starts and idles perfectly and runs great when not hot. As soon as the engine is up to operating temperature, it freaks out at around 2000 rpms and sets DTCs.

Random shutdowns are a bummer and can be a real project to track down. Flaky wiring, temperamental relays, etc. Could even be a PCM or ignition switch. If the PCM thinks there is no oil pressure, it will whack power to the fuel pump. I would start by monitoring fuel pressure if it were my car. Don't forget to check that famous stud at the underhood fuse box, either.
 

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Every optical sensor I have had go bad has set codes. Either or both of DTCs 16 and 36. One of the ones I have (currently for sale in an otherwise perfect distributor) starts and idles perfectly and runs great when not hot. As soon as the engine is up to operating temperature, it freaks out at around 2000 rpms and sets DTCs.

Random shutdowns are a bummer and can be a real project to track down. Flaky wiring, temperamental relays, etc. Could even be a PCM or ignition switch. If the PCM thinks there is no oil pressure, it will whack power to the fuel pump. I would start by monitoring fuel pressure if it were my car. Don't forget to check that famous stud at the underhood fuse box, either.

PCM doesn't give a rats ass about oil pressure. I have run LT1's with the oil pressure sending unit unpluged. Only this it does is engage the FP relay if for somereason the PCM doesn't send the signal to the relay.
 

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PCM doesn't give a rats ass about oil pressure. I have run LT1's with the oil pressure sending unit unpluged. Only this it does is engage the FP relay if for somereason the PCM doesn't send the signal to the relay.
How about that, you are right. I have been working with this later model stuff so much lately, I just said that without thinking. Sadly, I never took a look at the circuit until just now...and the fact that they would design it that way (relay and oil pressure switch are wired in parallel) makes absolutely no sense to me.

So, ignore what I said about the oil pressure switch...unless both it and the fuel pump relay are both malfunctioning at the same time :D
 
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