PLEASE HELP! I don't know what else to do on it

[jrnorton4]

Hi everyone, first post, and I need help. Bought an 82 with crossfire injection a couple weeks ago that had been sitting up for about 2 years. You can pour fuel into the throttle bodies, and it will crank and run like a champ, but will not put another drop of fuel out until its about to die. It will then inject from both injectors, just a second or two injection, sometimes stays running, most of the time dies on me.
I had a TBI truck in the past, and the fuel pump was the problem I experienced with it. The fuel pump was putting out 10 lbs, but I went ahead and changed it to an 85 vette pump and cleaned out the tank good. Filter was good. Nothing different up front. Fuel pump relay turned on with the key to pressure up, then started pumping good again when turning the engine over. Pulled both throttle bodies apart and checked the injectors, cleaned them good, put back together. Fuel pressure good at the throttle bodies. Adjusted TPS to .530 reading on multimeter. Checked codes and got a Code 15 and a Code 34. Installed a new MAP sensor, installed a new coolant temp sensor, installed a new ignition module. Checked all wires going into these sensors and they all seem ok. Cleared Codes. Still doing the same thing. Checked the oil pressure sensor wires, hot & ground are good, and during cranking its showing over 40 lbs of pressure on the gauge.
The guy I got it from said it was professionally restored three to four years ago, and I think Corvette South in Meridian, MS did most of it. Anyway, looks to be pretty well done from all I can tell. He did say that it had some kind of security system on it that shut it down on him once until he put the key in the door and did something. Tried that to no avail.
I know I'm going to feel really dumb once I figure out what it is. Would prefer to keep the fuel injection for gas mileage and longevity if possible. This is my first Vette, and I want to drive it! Please feel free to e-mail me. HELP!!! I am out of ideas!!!

 

[jimbil208]

Hello

When you turn the key on are both injectors putting out a good cone shaped shot of fuel. The when it is running they should continually be putting out a nice shaped cone of fuel. You didn't mention ECM maybe (but is doesn't sound like it)you need a new ECM. Did you try balancing the throttle bodies?

jimbil

 

[jimbil208]

Hello again,

Or maybe reading this may help.

jimbil208

HowStuffWorks "How Fuel Injection Systems Work"

 

[jrnorton4]

When the key is turned on they dont put out anything. The only time they inject is when its about to die from being started by pouring in fuel. When they do inject, both put out a nice cone of fuel like they are supposed to. Havent balanced them, but figured they needed to actually be running and working before I did it.

 

[jimbil208]

they should putting out a shot of fuel when he key is turned on

jim

 

[Hib Halverson]

Reading a generic description on "how Things work" is unlikely to help solve this problem.

Do you have the 82 Factory Service Manual, "jrnorton4"? If so, have you read the section on the car's EFI and the fuel supply system?

Also, you mention an aftermarket security system...have you removed the system and restored the OE wiring? If not, there's a chance (admittedly a slim one), if that sec. system is faulty, that doing so will get the car to run.

 

[jimbil208]

Maybe ur ECU is defective

Jim

 

[68 4 spd]

have you tried a noid light to check for good electrical signal to injectors if she runs on fuel poured in then spark and module are performing according to manual there should be 12 volts at a terminals of both injectors and the b terminals ground in ecm to energize coils if you get power with volt meter and noid light wont flash while cranking check connections back to ecm

 

[jrnorton4]

Thanks everyone for your replies. I havent tried the noid light yet, just figured since the injectors would come on when it was dying that the connections to the ecm out back were ok. Planning to check out the security system setup and try to trace out wires tomorrow night after work. Gonna try the dealership for a gm manual tomorrow, as the one I bought has been about 95% useless. Please keep brainstorming and helping, this car needs to run soon! Thanks again!

 

[bpassmore]

The factory manual is the only way to go in diagnosing that system and other electrical problems.

 

[jimbil208]

The manual is the way to go.

But did anybody notice that he said when he turned the key on there was no fuel from the injectors.

This would be an obvious place to start,as they do put out a good shot when you turn on the key.

Jim

 

[jrnorton4]

Sorry havent responded here in a while. Found the problem, I hope, after tracing and checking continuity on wires going to the computer. Old battery must have boiled out, cause acid ran down inside the ecm and fried 3 of the terminals between the prom and the ecm board. Got to replace both of them.

 

[Hib Halverson]

Glad you found the problem.