sandfantom

I just got a buddy of mines 3.0 rebuilt and and am the process of trying to get it started. I have been searching for the last few days and I have not found anything real solid on this problem.

The engine is in a 88 x-cab pickup with 4x4 and manual trans.

It will run off of the cold start injector for a few seconds then dies and will not fire no matter how long you crank. If you recycle the key, it will try to start again for a few seconds and die.

What I know.
I have fuel and the fuel pump has power when cranking.
I have spark, tested with spark tester.
I do not have injector pulse with noid light.
I do have power to the injectors.
Grounds are good unless I forgot to hook one up. I have 4, engine ground to battery, RH side rear of engine camshaft cap bolt, LH side engine to left fender, rear of intake to firewall via connector.
I understand the distributor sends signal to the ECM to pulse injectors, is there a way to test this. Pickups seem to be good.
All fuses are good.
Timing belt is new.
Cap, rotor and plugs new.

I finally found a copy of the FSM for this truck and did all of the tests. Everything checks out good except the resistance on 2 of the pickup coils in the distributor are high, over 300 ohms and I get no resistance when I probe the NE to E1 connectors on the ECU wiring harness (wires unhooked).
NE wire is good from ECU to distributor.

I am leaning toward the distributor being bad because of the high resistance, but I hate to shot gun one in as I guess it could be the ECU also.

Truck ran fine when parked about 5 years ago. Has been setting ever since.

This truck had an after market security system on it and buddy cut the wires and pulled it out. Can't really find any wires where they shouldn't be.

It runs good when it runs, just doesn't run very long.

Any ideas would be appreciated.

scope103

You're not trying to start it with the induction pipe to the air cleaner disconnected, are you?

The fuel pump gets power when cranking, but as soon as you let go of the key the COR gets closed by the VAF (when the VAF senses air flow). It's then the COR that's powering the fuel pump, not the key. So if the induction tube is disconnected (or there is another problem in the VAF-COR circuit) the truck will start (fuel pump runs with key to START) and then die in a few seconds (as there is nothing to keep the pump running.)

sandfantom

Induction tube is on and all clamps are tight. Fuel pump has power when cranking and running for the little time it runs.

sandfantom

So I take it no one has had this problem before? Just my dumb luck I guess.

scope103

With no injector pulse the engine can't run, not even for a few seconds. Does it have an injector pulse at first, which then disappears? (I personally find "noid" lights tricky to use, so you might have yours set up wrong. As you seem to have already figured out, the injectors are always connected to +12v, and are triggered by grounding the other side.)

The injectors are "timed" from the IGF signal from the igniter. Does your spark disappear at the same time as the injector pulse? It could be a problem in the distributor (but an intermittent problem like that doesn't seem too likely.)

Good luck!