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Discussion Starter · #1 ·
I searched and read a handful of threads but still need a little help. Please read all details.

1994 Corvette LT1, manual, OBD1, owned it for six years/ 62k miles, catback installed before I got it, otherwise stock. About 112k miles on the chassis, 30k miles on the engine. Original engine, just rebuilt. New AC Delco opti at time of rebuild from a Chevy dealer. ICM and coil are original (but appear to be working per below).

I started it tonight after it sat for about 30 hrs (daily driver), made it to the top of my driveway, it stalled fairly abruptly, cranks but will not start. It will pop a bit here and there; it’ll fire a couple of times, but won’t start.

Fuel pressure is 40 psi key on, within +/-2psi of that during cranking, holds with zero bleed down at 1min, and 2psi bleed down at 5 min.

Pulled the plug wire on cylinder 3 and connected a spark tester. Good blue spark at a regular rhythm.

Checked all fuses and found an interior lighting fuse and the air pump fuse were blown. Still no start.

Will not start on ether.

Opti appears to be dry from what little of it I can see.

No harnesses or vacuum hoses appear damaged or disconnected.

No codes (checked by jumpering pins 4 and 12).

I have neither an FSM nor scan tool.

For full disclosure it has been developing an exhaust leak over the last few weeks, not 100% where, but sounds and looks (soot) to be one of the joints by the X pipe (after all O2 sensors). I have been waiting until I get my welder back from repair (it’s always something) to address that. An inspection of the exhaust system does not reveal any holes, thru rust, or damage. I do not believe that anything has changed on the exhaust in the 100’ I drove it, and do not believe that it is causing the no start condition.

Thank you for any help you may be able to provide, I appreciate it.
 

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Well I have a 95 Corvette , as long as you are not getting the dreaded Opti code or for that matter , any codes. ( that is great news ) maybe check the chassis fuel filter under the Passenger door front end . I’ve clogged mine , and changed it out , problem gone ! Fuel gage on the rail may tell the story , but , not always . It’s a low $$$$ part to throw at it . That is easily overlooked and will leave you stranded . I hope that’s it buddy !!! Let us know !
Corvette wave 👋,
Robert
 

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Discussion Starter · #4 ·
The fuel filter is fairly new, but I believe I solved this, and you are on the right track.

I cranked it yesterday to see if the tach registered(indicating the distributor optical pickup pulse is good, which has already been proven… but…) it fired up. Ran like crap for a few seconds, then evened out and ran fine.

So I called my local shop that I deal to see about getting it in for a diag because now it was a dreaded intermittent problem, and I had the golden opportunity to bring it there without putting it on a flatbed.

They’re backed up for weeks, but said it sounds like bad fuel (water in the gas).

I let it sit for a few hrs so it could separate again in case that was what was going on (all the cranking may have have stired it enough) and pulled a three beer bottle sample of gas from the rail. I saw some water precipitating out of the gas, but it never amounted to much, not even a continuous layer on the bottom of the bottles. So I went to take an additional sample from the tank, and when I lifted the gas flap I found I to be full of water.

Now for those of you who aren’t familiar with C4’s the gas flap is on a horizontal surface. The cap sits down in a bezel under it pointing straight up. Next to the cap is a small drain hole in the bezel. Mine was clogged with tree seeds, and the bezel was full of water. The gas cap was submerged.

I never did pull any gas that had any appreciable amount of water in it, but it started three times over 24hrs. So today I put some methyl in it and drove it around town, without any issues.
 

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This is great news brother , I’m super glad that you pin pointed it !!! Man that deep hole must of been really clogged !!! I can in vision it now !!! Methyl , Okay !!! That’s a good one to put in my back pocket . I know a lot of guys on the inter web are making their own Race gas with Toylene , I know that the refinery’s use it as an octane boast . I have a brand new Golen 396 stroker and I’m scared !!! Lol 😂 I use the VP Race gas concentrate in all my tanks , a can of that brings 10 gallons of 92 to 101-104 octane every time ! Good stuff , it’s available at most auto parts and on Amazon . Maybe a can of that might help also . I will remember the Methyl for sure !!! Glad you got er figured out at the low $$$$$ end . Plus I respect any man that measures with empty beer bottles , as a matter of a fact here in about 15 minutes I will have a empty on of my own !!! Lol Corvette wave my Brother !!!!
GOD bless ,
Robert
 
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