91 corvette cranks but won’t start! Please help

[ThatRyanGuy]

So I picked up this 91 corvette about a month ago.

Ill list everything Ive done so far because I can’t fogure it out.
parts replaced-
1) battery 2) altenator 3) fuel tank sending unit 4) fuel pump 5) fuel filter 6) both oil pressure switches 7) fuel pressure regulator 8) ignition coil 9) spark plugs gauges to .035 10) smog air pump 11) serpentine belt. 12) bypass vats.

Done a fuel pressure test-48 psi drops to 40 psi after sitting on run for 45 minutes.
Used a Noid light tester for each injector and everyone pulses.

Car will crank rank but won’t start. If I use starting fluid in the tbi it will start but shuts off as soon as I stop fluid. Check plugs for spark, I have spark to the spark plugs.

The car sat sat for two years, the lcd display is corroded so I can’t read any codes off the dash. Check engine light and battery light comes on when trying to turn key. Security light shuts off when I turn the key. Goes solid when I lock the doors and blinks when I unlock doors to get into car.

What should i be I be looking for? I can’t figure out what my next step should be.

im open to any suggestions at this point.

 

[BigJimZ16]

Have you checked for spark at the plugs??

 

[ThatRyanGuy]

Have you checked for spark at the plugs??

Yes. I checked for spark yesterday when changing each plug out and the ignition coil.

 

[compyelc4]

So I picked up this 91 corvette about a month ago.

Ill list everything Ive done so far because I can’t fogure it out.
parts replaced-
1) battery 2) altenator 3) fuel tank sending unit 4) fuel pump 5) fuel filter 6) both oil pressure switches 7) fuel pressure regulator 8) ignition coil 9) spark plugs gauges to .035 10) smog air pump 11) serpentine belt. 12) bypass vats.

Done a fuel pressure test-48 psi drops to 40 psi after sitting on run for 45 minutes.
Used a Noid light tester for each injector and everyone pulses.

Car will crank rank but won’t start. If I use starting fluid in the tbi it will start but shuts off as soon as I stop fluid. Check plugs for spark, I have spark to the spark plugs.

The car sat sat for two years, the lcd display is corroded so I can’t read any codes off the dash. Check engine light and battery light comes on when trying to turn key. Security light shuts off when I turn the key. Goes solid when I lock the doors and blinks when I unlock doors to get into car.

What should i be I be looking for? I can’t figure out what my next step should be.

im open to any suggestions at this point.

Well, my first thought is you gotta get that thing towed to a shop that knows C4s. They'll get it running, maybe for less $$ than you are throwing at it.

 

[ThatRyanGuy]

Well, my first thought is you gotta get that thing towed to a shop that knows C4s. They'll get it running, maybe for less $$ than you are throwing at it.

Thanks the the advice Ted.
The idea is to get the car running without having to take it to a shop.

 

[LLC5]

So I picked up this 91 corvette about a month ago.

Ill list everything Ive done so far because I can’t fogure it out.
parts replaced-
1) battery 2) altenator 3) fuel tank sending unit 4) fuel pump 5) fuel filter 6) both oil pressure switches 7) fuel pressure regulator 8) ignition coil 9) spark plugs gauges to .035 10) smog air pump 11) serpentine belt. 12) bypass vats.

Done a fuel pressure test-48 psi drops to 40 psi after sitting on run for 45 minutes.
Used a Noid light tester for each injector and everyone pulses.

Car will crank rank but won’t start. If I use starting fluid in the tbi it will start but shuts off as soon as I stop fluid. Check plugs for spark, I have spark to the spark plugs.

The car sat sat for two years, the lcd display is corroded so I can’t read any codes off the dash. Check engine light and battery light comes on when trying to turn key. Security light shuts off when I turn the key. Goes solid when I lock the doors and blinks when I unlock doors to get into car.

What should i be I be looking for? I can’t figure out what my next step should be.

im open to any suggestions at this point.

If it runs with starting fluid then it sounds like a fuel/fuel supply problem. Start by disconnecting the fuel line to the injectors and run a hose to a bottle, bypass the fuel pump relay and check the fuel volume and the fuel itself. It could be dead/bad fuel or even diesel. Fuel pressure doesn't equal volume, you need to know the volume of fuel reaching the injectors, and you need to know that the fuel is good.

 

[Hot Rod Roy]

If it runs with starting fluid then it sounds like a fuel/fuel supply problem. Start by disconnecting the fuel line to the injectors and run a hose to a bottle, bypass the fuel pump relay and check the fuel volume and the fuel itself.

Since the car has been parked for two years or so, you need to get fresh fuel to the injectors. LLC5 has a good idea. You have good noid lights, so your ignition and f.i. circuits are good. The engine runs with starting fluid, so the only thing left is no fuel from your injectors! Your injectors need to be cleaned or replaced due to bad fuel clogging them, or the newer ethenol fuels damaging them. Fuel Injector Connection Fuel Injector Connection - High Performance Fuel Injectors has a very good reputation. They can clean and test them for flow and balance, or recommend the best plan for you.

:cool

 

[ThatRyanGuy]

Since the car has been parked for two years or so, you need to get fresh fuel to the injectors. LLC5 has a good idea. You have good noid lights, so your ignition and f.i. circuits are good. The engine runs with starting fluid, so the only thing left is no fuel from your injectors! Your injectors need to be cleaned or replaced due to bad fuel clogging them, or the newer ethenol fuels damaging them. Fuel Injector Connection Fuel Injector Connection - High Performance Fuel Injectors has a very good reputation. They can clean and test them for flow and balance, or recommend the best plan for you.

:cool

Update on posts.
Thanks everyone for all the feedback. I pulled the fuel rail off, replaced all injectors and she fired right up. Ran her for a bit but noticed a thermostat leak. Just replaced thermostat and gasket. Ran for the day. Came back the next day and now my cats bypass isn’t working. I’m looking into ordering a cats bypass from Eckler a corvette. My key pellet is reading 3.68 so I’m not sure if my key is a code 9 or 10. Any ideas?