Hello all I just recently bought a automatic 89 and with about 20k on it. Its been sitting for a long time so I'm dealing with a few things. As of right now all ive really done is replaced the fuel pump and sock. The fuel tank was super rusty so I gave it a good clean and I drove it home approx. 30 min drive. It ran a little rough and if you put it in drive or reverse it would run even worse and die shortly after if you didnt start to drive. The guy I bought it from said it probably needs to be timed so once I got it home I bought a timing light and watched a few videos on how to do it. I've got it set at 6 BTDC but now when I fire it up it dies shortly after in park. Not really sure where to go from here. Any recommendations would be appreciated thanks!

 

Did you unplug the EST wire

 

Yes the EST wire was unplugged and I disconnected the battery to clear any codes.

 

From what I'm reading it was acting up before and did you adjust the timing a lot? Me, I'd start with injectors. Probably full of rust.

 

I adjusted the timing around 3 degrees im pretty sure. It was acting up before i adjusted timing but it still ran in park just fine before now it dies out withing a minute I'm gonna take a deeper look at the rest of the fuel system but the guy I bought it from put on a new filter and injectors so I didn't really think they would be the problem.

 

Congrats on your new vette.
It seems to me the previous owner was trying to find the problem as well. New injectors and filter then it sat for a long time and then he sold it. I think he was hunting the same problem and gave up. His use of the words "probably needs timed" can be tossed out as wishful thinking.
In trying to find your problem, I would recommend during your trouble shooting that you do one thing then stop. Then test it thoroughly. Do not take a lot of things apart if you do not have to. This guy was hunting something. Codes can be very helpful, learn to get the codes from the computer. There are some things that are suspect. How did it run at speed on the way home? And as a side note, replace the brake fluid in it as soon as possible. And expect possibly more than one problem.

Previous owner bought junk injectors, send us a pic of the injector part number. They can be photographed in place.
Vacuum leaks , vacuum leaks make the L98 run like crap.
EGR valve stuck / is service engine light on ? Codes ?
Get a fuel gauge and check fuel pressure. Even if replaced there are plenty of junk/bad fuel pumps on the market.
Fuel pressure regulator, pull the vacuum line off and see if you smell fuel. It should be dry and oderless.
Do you have a FSM field service manual?
IAC idle air control valve
MAF sensor problem, check the air filter as well.
Check #1 cylinder for top dead center as harmonic balancer may have slipped. Where does the bull nose (notch) point on the distributor? Does it point directly toward the left fender 90° away from the nose of the car?

 

Thanks! You put alot in here and I really appreciate all of it firstly after some looking i noticed before I try starting the car the injectors make a weird kind of ticking sound it only happens for around a minute. Also I took a picture and tried to fine the serial numbers for them but I can't. I've attempted to look for vacuum leaks and came up with nothing I'm not really sure where all of the vacuum lines are so I just looked at all of the hoses I could see. The SES light is on but when I put a paperclip into the A and B connectors nothing happens it doesn't even go into diagnostics mode. I doesnt flash at all. It did before this but not now. As for everything else you listed its all a work in progress I get to all of those things.

 

So i got it started after cranking for awhile and giving it gas but it dies around 5 minutes of running. The fuel pressure sits at 40 psi pretty much the entire time. Here is a video of what it sounds like running and what it sounds like after trying to start it again.