Ok, we checked everything once again last night.
Still more questions:

1. Tach is still buried at max position. Disconnected the line from the distributor, re-connected and still all the way up.

2. What does the fuel pump relay look like? I have 2 multi-wired black plugs and one metal clad unit behind the passenger seat, but none look like the same color wires for the fuel pump. Some of these are probably
for the amp/radio set up. With key on, no juice at the fuel pump.

3. We hot-wired the fuel pump, and it is working. While it was running we
tried to start the car, and can hear fuel at the intake manifold, but cannot
get a pulse to the TBI's. The pressure seems very low as well. We have
an electrical pulse, but the fuel is not getting thru. Sprayed some Gumout into the TBI's, and the car ran for a few minutes until the Gumout burned off.

4. Checked the 20 amp fuse above the battery, all looks normal.

5. Disconnected the low oil pressure switch on the intake, and car still will not start.

Could it be the ECM?

Is it time to flatbed the car into the shop?? I am Bummed... :cry

 

fuel pump relay is the box w/ the red, orange, black/white & green/white wires coming out of it.
There are 2 3amp fuses on the fusebox for the injectors: Inj1 & Inj2


However, it sounds like you have a bad shortage somewhere that is zapping the entire system. i think there's voltage on a wire somewhere that is making the tach go to max. position (probably a 12V shorted to the system ground). If it does that the ECM can not ground the injectors, needless to say they won't fire (they are controlled by grounding, there's a constant voltage on the pos. side)

Check all the pinouts (this is an 84 connector, the 82 is the same)

Some may vary a lot or be 0 since you can't run your car but look for excessive high voltages on signal wires or grounds. It should be pretty obvious if something is not right.

I've seem something like this before only once and it was a shorted out TCC solenoid. UNplug it from the transmission (or disconnect the connector in the engine compartment, it's near the distributor, coming out of the firewall enxt to the steering column, the rest of the harness goes down towarads the tranny under the wiper motor and over the bellhousing)

This is a serious problem you have here, I suggest you try to find it yourself, having a shop do this is very expensice since these electrical problems are a PITA to diagnose.

Marck

[Modified by Twinnie, 7:14 AM 9/18/2002]


[Modified by Twinnie, 7:22 AM 9/18/2002]

 

Thanks Twinnie,

This is great info. Will give it a try.

 

Also might consider replacing your ignition module (the one IN the distributor) if you haven't already. They're known to go bad once in a while and can cause havoc as well.

 

Yeah, and if the module doesn't put out a cranking signal the ECM won't fire the injectors.

 

BTW, a problem w/ the module van be a PITA to diagnose. Since there is no cranking signal it DOES trigger a fault code, code 12. However this code is already tripped w/ the ignition in the on position. (W/ the ignition in "on" the FI system works like w/ the engine running, only there's no cranking signal and no injector firing. This is a result from the way the system is designed. Code 12 is used to see if the diagnostics work but it actually is a genuine fault code for the crank signal and if the module craps out there's no way to see if the fault code was valid or not)

Marck

 

Peter, I had the same problem. The relay is behind the DRIVERS seat between the ECM and seat area. it is 2" x 2" and black. I replaced this and it still would not fire. Replaced the Ignition Module and then I was in business. Email me if you have anymore questions.
Chris

 

The ESC is located between the ECM & the seat area. There are several black boxes, the largest one on the back of the ECM is the ESC, the smaller 2"x 2"one is the EST, the smallest one w/ 2 ears on the side is the relay. It's just a normal relay like many found in the engine compartment. I'd take a pic but don't have the camera here (I have the relay in front of me)

Marck

 

Check the ground cable to make sure the system is charged and grounded. the electrical system won't function if there isn't a good ground.

 

Thanks for all your replies.

Does anyone have a wiring diagram for the fuel system??

My mechanic asked me for a copy so we can troubleshoot.

Email to me at competent@worldnet.att.net, or fax to 973-808-6644.

Appreciate all of your help.

 

Hope you don't have dialup:


If you put these together they form the entire diagram for the system.