About the knock sensors keeping the car from starting.......I once failed to rehook the sensors up on my 92 after some engine work. The car fired up but went immediately into the "limp home mode". So I would say the definitive answer is yes, the engine should at least fire up. My $ is on a bad ECM.

 

OK BLM's should be ~128 your running a little rich.O2's should average ~800 when heated once again mabey too cold to heat them up enough but it said it was in closed loop.The O2's will jump all over the place at any time that is why you need to look at the average.Overall I see nothing that stands out from your scan I see no indication of knock besides the going down to 18* during miss might be one but knock retard is a momentary thing.I use Datamaster and it shows even momentary knocks.I hate throwing parts at my car but if you can borrow someone else's ECM to check if yours is the source.Did you reset your codes before the scan and the 41 came back?

 

Im at the end of my rope. Started car to check for carona effect, no leaking wires. Car smoothed out at idle and at higher rpm....... seemed to be running perfect again. Let it idle for about 20 nimutes to let it come up to temperature and settle at 182 degrees. Engine ran and idled fine without amy missing and tach was steady at 650 to 700 rpm ( no tach needle jumping like before during test) and everything seemed fine. Decided to tale it for a teat drive about one mile, tutned around to come home and half a mile from home went to about 3/4 throttle. Engine immediately sputtered and died and refuses to start back. Lucky to find a parking lot to pull off into and waited about 1/2 hour and tried to start it many times. Sometimes kicks like it wants to start, other times just rolls. WILL NOT START BACK UP so I had to leave it and hitch a ride back home.
I live in the Cayman Islands and the only two other 92 LT1 on the island got drowned with salt water September last year during Hurricane Ivan ( mine was dry in the garage) so no chance to swap ECM with anyone. My wife just happens to be in Miami Christmas shopping this week so I have taken both of your advice and asked her to pick up a new ECM and knock sensor at the GM dealer up there and bring it back on Saturday. If this dont fix it I'll replace the Opti.
Im new to corvettes ( had 9 camaros before tempted to go back but the Vette is so sweet when she runs right ) and this forum, Does anyone know fo any 92 LT1 Gurus on this forum that I could ask to join in on this discussion?
Unless anyone has any further teast that I can do I have no choice but to start throwing parts at this problem. Neither the local "corvette mechanic" or the local GM dealer have been able to give me a good diopnosis and searching the forums on the internet has not produced the answer .......... Im at the end of my short rope.
Thanks everyone for your patience and help.
Jerris
PS I cleared codes each time and code 41 kept coming back

 

I use to have a few problems with my 92 . It would run fine but sometimes it wouldn't start, especially when ECM got hot. I purchased a used ECM on Ebay for 50 bucks and lo and behold no more start up problems.

 

ttt

 

Do the ECM since you have little tech support but if it does not work get a Helm Factory service manual http://www.helminc.com/helm/welcome_...PDCMNC9DWQ4315
And start trouble shooting the codes according to the steps.I would wait on the Knock sensor it is best to do 1 at a time to ID the trouble.The Knock sensor will not prevent start up anyway.It is not unusual for a new opti to go bad either so if the ECM swap does not work that is where to look.That and the wiring.If it is like me it is probably some dumb little thing that is just evading detection.You will get it just eliminate one thing at a time.

 

If you are getting no code 16 (Opti low-res error), and are getting no spark out of the coil, forget about the Opti, as it's not your problem. The ECM can run the engine with the high-res pulses absent from the Opti, but not with the low-res pulses absent. If the low-res pulses are absent, you'll get a code 16. If there's no code 16, the optical section of the Opti is functioning at least well enough to start and run the engine. If there's a problem in the high-voltage (distributor) section of the Opti, you'll still get spark out of the coil wire. If no code 16 is present, and no spark is present at the coil, stop worrying about the Opti, because it's not causing your problem. Look elsewhere.

My best guess is that the cause of your problem is either:

An intermittently open connection in the ignition control circuitry -- inspect all connections between the ECM and both the ICM and Opti VERY CLOSELY. I'd say there's a good chance there's a corroded/bent/recessed/sprung contact in one of those connectors.

Or:

A faulty ECM that is unable to communicate with the ignition control circuitry. The new ECM your wife is bringing back should solve this.

Best of luck, and keep us posted on how you're making out.

Be well,

SJW

 

I think I found one of the proplems, the plug in on the opti was a bit loose and needed cleaning, at least I was able to duplicate the no fire at idle and make the car die by moving the wires to the plug around with a long screwdriver. Took off the plug, cleaned it and closed the sockets for the pins some to give a tight fit. Engine now starts every time, however when it warms up it starts to rum badly, tachometer jumps around, idle wanders, miss and sometimes shuts down from idle, but at least I have spark. Im afraid to test drive it on the road like this before I have to leave it again.
They had to order in the ECM in Miami so I wont get it until Thursday by Fedex. Ill swap the chip and plug it in and hope this is the end of my problems. In the maintime I will clean up all the other connections in the ignition circuit. Thanks for the tips on the opti, I will leave this as a last resort. I also have a helms manual coming in with the ECM.
Thanks for your patience, I will keep at this until I have it sorted out and keep you posted on the forum.
Jerris

 

I fimally got this no start and bad miss when warmed up solved, thanks for your patience and all the helpful tips guys. Still waiting on the helms manuels to arrive ( will be here on Friday UPS) but the ECM arrived and I had the same problem.
Decided to take your advice and double check all of the connections between ECM and ignition that I could trace without the manual and finally found that there was two of the wires to the ignition module that was broken inside the plug on connector and before the pin.
Found that these two wires made connection most of the time but when hot and with the engine vibrations, was was loseimg contact.
One was causing the tachometer to read wrong (hence the reason for the ECM hunting up and down searching for the correct idle RPM) and the other would cut off the ignition altogether (hence the sparodic miss and the no fire for startup).
I soldered on a new connecter and PROBLEM SOLVED.
Thanks again for the encouragement guys and a word to others with a no start or miss problem like mine to start with the simple things and check ALL of the connections before throwing parts at it like I ended up doing ( New ciol, new ignition modume, new ECM ) :o
This forum is great
Jerris

 

ttt FYI

 

Another happy ending.Those connector are notorious.Told ya it would be some dumb little thing.