Codes 1371 and U1F with 'new' Opti...
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There is no IC Module internal to the Opti that I am aware of. The IC Module is on the bracket on the front of the driver's side head. That can heat soak. Shoebox has a "fix" on his site.
Both the IC Module and the Opti optical module are solid state devices. When they overheat, various components can have their operating characteristics altered by the temperature. The module shines tiny LED's through the slots in the wheel. The receptors on the opposite side of the slot produce a voltage when light is detected, and no voltage when no light is detected. The module will have to amplify this signal to produce the two square wave pulse output signals.
Both the IC Module and the Opti optical module are solid state devices. When they overheat, various components can have their operating characteristics altered by the temperature. The module shines tiny LED's through the slots in the wheel. The receptors on the opposite side of the slot produce a voltage when light is detected, and no voltage when no light is detected. The module will have to amplify this signal to produce the two square wave pulse output signals.
So I'm not ruling out the IC module on the head, but failure of this wouldn't set a 1371 code, right? The 1371 is specific to the optical crank sensor?
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P1371 if for the low resolution pulse pattern, which is produced by the optical module. The question is, how often does it appear after the engine shuts down? If its been cleared, and reset every time the engine shuts down, it is a problem somewhere between the optical module, where the pulse pattern is created, and the PCM. Could be dirt in the optical module, heat soak in the optical module corrupting the pulse pattern, a bad connection from the Opti to the PCM.
If the code is not always there when the engine shuts down, the code may just be setting spuriously when the engine is starting, and the PCM is trying to find the pulse pattern. I've seen that code present in many data logs where the optical module is not failing. In that case, something else is shutting down the engine. Heat soak of the IC Module would be a viable explanation. Its one of the best I can think of, but not an absolute certainty.
It comes down to how ofted the code sets, and whether it correlates directly with the engine sudden shutdown. You have to scan it after each event, and clear the code after you hve scanned it.
If the code is not always there when the engine shuts down, the code may just be setting spuriously when the engine is starting, and the PCM is trying to find the pulse pattern. I've seen that code present in many data logs where the optical module is not failing. In that case, something else is shutting down the engine. Heat soak of the IC Module would be a viable explanation. Its one of the best I can think of, but not an absolute certainty.
It comes down to how ofted the code sets, and whether it correlates directly with the engine sudden shutdown. You have to scan it after each event, and clear the code after you hve scanned it.
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Registered User
Joined: Nov 2003
Posts: 570
From: NC
P1371 if for the low resolution pulse pattern, which is produced by the optical module. The question is, how often does it appear after the engine shuts down? If its been cleared, and reset every time the engine shuts down, it is a problem somewhere between the optical module, where the pulse pattern is created, and the PCM. Could be dirt in the optical module, heat soak in the optical module corrupting the pulse pattern, a bad connection from the Opti to the PCM.
If the code is not always there when the engine shuts down, the code may just be setting spuriously when the engine is starting, and the PCM is trying to find the pulse pattern. I've seen that code present in many data logs where the optical module is not failing. In that case, something else is shutting down the engine. Heat soak of the IC Module would be a viable explanation. Its one of the best I can think of, but not an absolute certainty.
It comes down to how ofted the code sets, and whether it correlates directly with the engine sudden shutdown. You have to scan it after each event, and clear the code after you hve scanned it.
If the code is not always there when the engine shuts down, the code may just be setting spuriously when the engine is starting, and the PCM is trying to find the pulse pattern. I've seen that code present in many data logs where the optical module is not failing. In that case, something else is shutting down the engine. Heat soak of the IC Module would be a viable explanation. Its one of the best I can think of, but not an absolute certainty.
It comes down to how ofted the code sets, and whether it correlates directly with the engine sudden shutdown. You have to scan it after each event, and clear the code after you hve scanned it.
I honestly haven't checked the codes since the first day this happened so I'll do that and carry the scanner with me to check every time.
Like last night I drove it around about 2 hours, errands and a miniroadtrip. It stumbled one time on the way home at the end of my trip, but didn't actually die.
Also my MIL light doesn't work so I have to actually scan it to see if any/new codes set. Gotta fix that. Too.
Thank You Sir *I Love You*!!! (But not with the Ghey...)
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OK so 7 times on the way home this evening... I had the scanner with me, each time it died, I cleared the codes. Each time it set 1371 and only 1371. 7 times in less than one hour.
So if it was the IC, wouldn't it be likely to be setting a misfire code or codes as well?
Also I called Summit today and I did buy the Summit brand, which I think is a reman unit.
They're willing to refund the price of the Summit unit if I pay the difference to get the GM Performance new model, ~$100. I think that's what I'll do. Is probably what I should have done to begin with.
So if it was the IC, wouldn't it be likely to be setting a misfire code or codes as well?
Also I called Summit today and I did buy the Summit brand, which I think is a reman unit.
They're willing to refund the price of the Summit unit if I pay the difference to get the GM Performance new model, ~$100. I think that's what I'll do. Is probably what I should have done to begin with.
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It's a little maddening... Nearly $400 to put a stock opti in it... $700 for a decent ignition upgrade... For a 13 year old Camaro with essentialy a small block chevy under the hood...
Makes me seriously consider reviving my Malibu... HEI and a Holley... No worries... Also 10mpg but still...
Makes me seriously consider reviving my Malibu... HEI and a Holley... No worries... Also 10mpg but still...
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So, wait, why isn't the Crankshaft Position sensor in question here as well? If I'm reading the manual correctly and/or seeing it's location correctly (bottom of the timing cover) it is intertwined with the optical sensor in the distributor itself.
Wouldn't the crankshaft sensor failure also set a 1371? When I read the manual's troubleshooting for 1371 it doesn't investigate the CKP.
I have to be missing something...
Wouldn't the crankshaft sensor failure also set a 1371? When I read the manual's troubleshooting for 1371 it doesn't investigate the CKP.
I have to be missing something...
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Oh, and, this was 'fresh' in that I just did it a few months ago, and all the bolts were clean and everything went smoothly, but...
I'd say ~6 hours total wrench time. Really not as bad as I thought it'd be. Last time I had the motor/trans completely out so it was a whole different job...
I'd say ~6 hours total wrench time. Really not as bad as I thought it'd be. Last time I had the motor/trans completely out so it was a whole different job...
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