Problem starting engine that hasn't run for 3 years
 

I have put a LS1 from a 2003 Holden into a 81 Corvette and have been trying to start it today. When I try to start the engine cranks but kinda pops and and there is a little bit of smoke coming out of the exhaust. I have only tried to crank it for a few seconds at a time.

I had the spark/injector and pump fuses pulled and cranked the engine for 10sec about 3 times before starting to try and get the oil moving a little before hand.

I have scanned the car and it not showing any DTCs.

The fuel system is definitely pumping. I am fairly certain I am getting power to the coil packs and injectors. The injector were pulled and cleaned about 6 months ago but then put back in the engine. The car has headers but no exhaust system and the O2 sensors aren't connected.

Any ideas at what I should look for? Any particular things I should monitor with HP tuners scanner during cranking?

I have read a few posts about things to maybe try. Should I do any of the following:
- Remove all plugs and crank engine with no compression?
- Bleed fuel rail?
- Pull fuel rail and crank to see if injectors are firing?

Thanks for the help.

I know it is probably irrelevant to starting but we compression tested each cylinder a few months back and they all looked good.

I have had issues with injectors sticking from sitting a long time.

Is there anything I can do to unstick them? They were cleaned 6 months ago and had new filters installed but then were put straight back on the engine with fuel sitting in the rail.

I have flushed the fuel lines before connecting them to the rails on the engine.

Do you think I should perhaps try and pull the fuel rail, unstick the plugs, reconnect everything and then bleed the fuel rail?

Prime for a minute and bottle feed till it fires.

you said " fairly certain" that the injectors are getting power. When i first tried starting my car, it did the same thing. As soon as it first started to spin it would pop then nothing. Long story short. The wire i was using to power up the computer was not feeding a full 12 volts (around 3-4 volts) when cranking. It had a bad connection on the fuse block. Corrected the problem and BAM first try. You may have already checked this but it is worth a look. Check the computer grounds for "breakdown" too. these are really sensitive to grounds.

If you suspect stuck injectors, I have had luck unsticking them by using jumpers to activate them directly from the battery. A few cycles is all it takes.

Soak in kerosene and then rinse in Coleman camp fuel. 30 minutes each.

get a 194 bulb. bend the prongs straight to where you can insert into an injector plug. turn engine over and see if the bulb lights up. It should flash on and off when its firing. Sorta like a spark plug. That will diagnose the injectors getting fire or not. If you got fuel and fire it should start unless you got a crank sensor or cam sensor thats bad. Your probably not going to find a DTC if the computer was not powered up for a long time.

Ok I just used a 9V battery to pulse the injector manually and I think they are probably stuck.

One of the injectors makes a decent clicking noise when power is pulsed, the other 7 are barely audible at all. From memory after they were cleaned they all sounded like the one that is clicking so I suspect that I have 7 stuck injectors.

Since they have already been cleaned and had the filters changed I don't want to send them off anywhere to be cleaned again, so what is my best option for fixing them at home? What is the trick with boiling them? Just suspend the tips in water whilst it is boiling and then maybe pulse them with the 9V battery a few times? What's the best way to get the water out after as well?

They are definitely getting a good 12V from the fuse box, same with the spark plugs.

I pulled mine out and soaked them in fuel injector cleaner. I then pulsed each one with the 9 volt battery while blowing compressed air through them. Have not had a problem and I have never had a problem with the fuel rail being air locked. Seems that if the injectors are firing the air would go right past the injectors and bleed the fuel rail.

Just finished fixing all the injectors.

4 of them came unstuck just by chucking them in boiling water for 2min and then pulsing them with a 9V battery. The other four were a bit stubborn and need to be boiled a little longer and then pulsed with a car battery.

I then rinsed them all in some fuel and put them back on my rail and connected the fuel line but didn't put the rail back in the engine. After running the fuel pump to pressurise the rail two of the injectors were leaking slowly. I pulsed them a few times and kept re-pressurising the rail until eventually at full pressure there was no signs of leaking.

Everything is back in the engine but it is too late to try to start the engine here since it has no exhaust apart from the headers and my neighbours would go nuts. Hopefully tomorrow everything should fire up ok.

Should I pull all my spark plugs and crank the engine over a few times to move the oil about before trying to start again?

Always a good idea IMO.

How did it turn out? did that sove the problem? i have some "stuck" injectors that i might be able to save.

After cleaning the injectors it started like it had only run yesterday. No problems at all.

I would make sure after you unstick the injectors that you put them back in the fuel rail and but not back in the intake and then pressure test by running the fuel pump. If I hadn't done this I would have had two injectors filling their cylinders full of fuel on startup. Could have resulted in hydrolock

Good deal. :)

I love a happy ending.

Where are the burn out videos?