Well,.fate has a way of being a pain in the ***.

Was taking the C4 out to a track day today at Sebring. Put new track spec.pads and stuff on, good fluid in it, ready to rock and roll. Drove it to work yesterday just as a shakedown, everything seemed fine, though I thought it felt a little sluggish. Chocked it up to being my slowest car and no big deal.

Picked up the trailer to bring it out to Sebring, was working on loading it up, engine dies. Weird, as I had recently redone the optispark with one from O'Reilly's, but ignored it, and got it ready to put on the uhaul trailer (not as easy as you'd think btw). Neighbor came over to provide some ideas to keep from bottoming out, as he was talking the motor died again. Two times made a trend, and I lost trust in it. Pulled into the driveway and let it idle, it died again. Pulled codes , high resolution opti fault. SOB.

So anyways, the parts store Optics are in fact not that great. Luckily it's lifetime warranty so I can get another free one, but it's still a real pain in the ***. And who knows how long that one will last. This one lasted months, not years.

 

I'm in the same boat. Replaced it with one from oreillys about 4k miles ago and mine is dying already. I won't put another one in, going with Petris. I plan on upgrading this engine at some point, I learned my lesson, might as well do it right.

 

I can't bring myself to spend $500 on an optispark. I might take this next one from O'Reilly's apart and loctite the bolts, I suspect that's what went wrong.

If I didn't have a 92 I'd buy Torqhead and be done with it forever. I emailed them today and they said they'll eventually have an optispark delete for the 92, but not the LS PCM conversion. That's just as well, I'm fine with the ECM I have now if I can get rid of this damn optical sensor.

 

Are there any other codes? Like H41 in Module 4? ( 4.H41 is ICM, and 41 will indeed stop the engne.)

I believe that you have a 1992 like I do. My understanding of the 92-93 is that the Hi Res signal isn't used for anything that keeps the engine running. The Lo Res (Code H16) is used for ignition trigger and timing. It needs Lo Res to control the ICM. When my opti died I had H16. I'd clear it, crank it, and H16 came right back. I pronounced the Opti DOA. I went with a Petris.

I just thought of a possibility where H36 could be associated with the engine stalling. While the engine is turning (cranking speed counts), the ECM compares the two opti signals / codes 16 (Lo Res) and 36 (Hi Res) to each other. If one signal 'drops out' or is not present at all for a certain number of pulses while the other continues, the one that dropped out sets its code. This is why opti codes are always displayed as History, because the Current code can only be present while the engine is turning. With the engine stopped, the ECM can't compare them to each other.
What if the Hi Res dropped out just prior to the Low Res also failing? Code 36 would be set, then the Low Res failed (which kills the engine) but 16 never had an opportunity to set, because Hi Res failed first and there was no Hi Res to compare Lo Res to to set 16? It might be an interesting exercise to clear the Module 4 codes, crank it (with a no-start) and see which opti code comes back.

I don't believe I've ever commented on your choice of supplier for your distributor. To each their own. But these optis aren't the distributor in an L98. They can't be changed in 15 minutes without having to also drain the coolant and get under the car to bang the balancer off. Because of the way I use my 92 (cross country trips of 1,000+ miles per day on a tight schedule) reliability is my primary concern. I don't want to have to change an opti in front of my motel room, nor have to do it again on the same trip when the parts-store unit fails.

I'm sorry your Sebring trip was ruined. These stupid opti failures cause collateral damage such as ruined trips, lost time, inconvenience and expense beyond just the cost of the new distributor. You rented a u-haul, bought brake pads, possibly reserved motel rooms, etc. Yeah, the replacement opti may be "free", but at what cost in the future when it fails again, and ruins another trip? Think hard about biting the bullet and using a Petris. I'm at 30,000 miles on mine in about 30 months. Opti troubles (and a ruined trip or schedule because of it) aren't even on my list of concerns.

Fix it and go tracking. Cheers.

 

I'll have to check the codes again. Oddly enough, every time it dropped out it fired right back up. That was not the case in my previous Opti issues, and also my previous opti issues it would only cut out at idle, it would sometimes almost die at like 2500 rpm but then catch itself and run more.

I was lucky enough to get almost everything refunded, but your point is well taken. I basically wanted a PTO day, and haven't yet gotten confirmation that I'm going to get my hotel stay refunded. $500 to avoid that is definitely preferable to wasting nearly that much in track fees and hotels and whatnot.

I'd really like to eliminate the opti entirely. Doing something like an LTCC with the Torqhead crank sensor providing the right timing for the stock PCM would be ideal, but that's likely more than just buying the damn Pettis Opti, and allegedly is reliable. t the end of the day, it's a track car, and a more expensive solution that's not going to be any more reliable doesn't really get me anywhere.

 

As I said above 36 should not cause a stall because the hi res is not used for anything that makes the engine run.

I won't condemn an opti if only H36 is present.

When you have time to futz with it, hopefully it won't start so that what ever is wrong with it is staying wrong with it so you can find it.

 

the parts store optisparks are crap

theres petris , but isnt it like $800+ or something stupid

look hard and you can still find OEM ones on ebay


convert gen 1 to gen 2 style and you’ll have nothing to worry about (except for the 1 guy on here telling me his bearing died on a gen 2 one)

 

Just buy the best option or have yours original from the mfg rebuilt . Is there not some one on this site that rebuilds them. I will look up his name if you need it done. Also I have three in stock may be you should also

 

Put one from autozone on 15 years ago, it started misfiring bad enough to break the starter (twice) about ten years in, did the coil near plug conversion and it's been fine since then.
I'm pretty convinced that if it's not soaked in oil or coolant and the high voltage isn't running through there it's as fine as any other similar sensor on an engine.
Bout 150K and change on it now, 250Kish on the motor in total. I wouldn't have a stock one, from anyone.

 

See, I don't think the high voltage is an issue on mine. I think it's just the timing portion of it. Honestly, I bet if I were to open it up, I bet the little wheel the sensor reads is rusty and loose.

I'm gonna just bite the bullet and order a Pettis. Maybe they'll run a black Friday deal? Probably not, but I don't have any track days scheduled now so it's a moot point I guess lol.

 

I think the high voltage in there makes it a more hostile environment for the sensor in the long run. Moisture and oil are another matter entirely and it's still not an awesome idea, but getting the ignition voltage out of there is a step in the right direction I think.
I'd still prefer a magnetic pickup but that's getting into real money to make happen. I've had pretty good service out of this one. I bought an L98 car not long ago and one of the first things I did was replace the pickup and the module, they fail about as often as the
optispark in my experience. Fluid ingress notwithstanding. Ain't no free lunch, the sensors fail on the LS too, and every other engine.

 

I asked Torqhead that same question for the 92/3 LT1, when I had my 93. This was back in 2017. So, I wouldn't keep my hopes on that.

Currently running a petris in my 96. Haven't put many miles on it, so can't speak for longevity.

 

On our 96, we’ve never had any Opti issues with (still running original at 63k) but did replace the cap and rotor on a cam swap project.

We also have a 94 with original opti at 125k. Recently converted it to vented but it’s still the older spline drive. That one threw an H16 a while back. On a whim I replaced the opti harness with OEM and so far the H16 has not returned.

 

OPTI are strang they can't tell time or milage ,just replaced one in my 93 LI-1 150,00 miles 2- in 4 years and these were not the cheapees ,made in the US about $250.00 ea two years is all I could got out of them so went with the I hope better Petris brand and yep not cheap ,I do my own labor and fixing to give myself a rase so not not sure after the rase I can aford myself any more LOL so hoping for the best .. I see all the time ( how long these OPTI last ) well who knows had a 95 LT-1 37,000 OPTI stoped working ,The pic of the old OPTI that 120,000 and ran great ,I guse refreshed the ols LT-1 and yep the OPTI can out ,PROOF thes OPTI are just who knows ..

 

I feel very lucky to have bought a rebuilt 96 vented opti from the Optidoctor. I then had him rebuild my original. I have it on the shelf but don't expect I will ever need it. Dan

 

Guys. It might not be the distributor. He does not have H16, and it fires right back up after the stall. << Both of these are not typical of an "opti failure".

He needs to conduct diagnostics.

 

Sigh. That's like... WORK though. Codes below while I look up what they all are. All H codes obviously.

1- 27 32 34 36 38 51
4 - 64
9- 83

 

Ok, looking those codes up has me more confused. The LCD codes makes sense to me, I replaced the polarizer recently and cycled it a few times without the gauges in. The map one is a bit odd to me, as is the EGR. I don't think the EGR one would shut it off, but maybe the MAP would? Dunno, but the MAP seemed fine, Indo have a custom intake and I believe I soldered extra wore into the MAP connector harness to move it... But that was a long time ago and frankly I don't remember.

 

Clear the codes and see what comes back.

 

[QUOTE=FAUEE All H codes obviously.

You must pay attention to the Module the codes are appearing in. You're confusing yourself needlessly. Yes, "32" is EGR, "34" is MAP, and "36" is opti hi-res, but only if they appear in module 4. Yours are in Module 1, which is the CCM. They are LCD codes.

1- 27 32 34 36 38 [color=#2980b9]>> All associated with the LCD. Can be set with the key ON with the cluster removed. As you said you did. (Module 1, CCM)

51 >> Invalid Key Detection. This is the "VATS" code. The resistance was wrong. Would result in a solid ON SECURITY light, and wouldn't start for the 5 minute timer. Can also be set if the IGN circuit is energized without the key in the cylinder. (Module 1 CCM)

4 - 64 >> Lean Right Bank. (Module 4, ECM)

9- 83 >> Low Brake Fluid Level (Module 9, ABS/TCS)

The "H36" you found initially appears to have been in Module 1, which is actually one of the five LCD codes. (You set them all with the key on with the cluster out.)

The opti codes H16 and H36 are in Module 4, the ECM. You don't have any opti codes.

There is nothing in those codes that was set by the distributor. Something else caused the stalls.