OPTI question HELP
Thread Starter
Intermediate
Joined: Feb 2005
Posts: 28
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OPTI question HELP
My 94 LT 1 opti might be bad. I've read alot of threads about bad opti. Mine start just and runs great until it warms up. At that point it hardly runs backfires spits misses and I get codes 36 42. Let it set and cool off And it will run great again. If I need to replace it I think the stock GM would be best. Is it BAD Is GM the way to go. THANKS for anyones input.
Le Mans Master
Joined: May 2005
Posts: 7,301
Likes: 2,222
From: Central Maryland
Code 36 indicates that the high-resolution signal from the Opti is not arriving at the ECM as it should. This means that either there's a problem with one of the optical sensors in the Opti itself, or there's an interruption in the signal line feeding signal pulses from the Opti to the ECM. Most likely, it's the Opti itself, but it could be a corroded connector, broken wire, etc.
It's interesting that you're also getting Code 42, which indicates a fault with the Ignition Control Module circuit, if I'm not mistaken. I've never heard of these two codes occurring together. You might want to try swapping out the ICM first (and check out all of the wiring to/from it), rather than diving into an Opti swap right away.
The '94 LT1 still used the Gen-1 Opti. They were highly deficient from a reliability standpoint, and as such, I'd highly recommend you consider either the DynaSpark or the MSD as a replacement, rather than installing another OEM Opti, if you end up swapping out the Opti.
Be well,
SJW
It's interesting that you're also getting Code 42, which indicates a fault with the Ignition Control Module circuit, if I'm not mistaken. I've never heard of these two codes occurring together. You might want to try swapping out the ICM first (and check out all of the wiring to/from it), rather than diving into an Opti swap right away.
The '94 LT1 still used the Gen-1 Opti. They were highly deficient from a reliability standpoint, and as such, I'd highly recommend you consider either the DynaSpark or the MSD as a replacement, rather than installing another OEM Opti, if you end up swapping out the Opti.
Be well,
SJW
