our 89 trooper won't stat. we've changed the relay, the fuel pump, the dist.cap and rotor. Our problem , we believe is electrical somewhere. If we directly connect the red and the black wires from the fuel pump to a battery it will pump gas, however when we connect the wires back to their appropriate wires there is no juice. the tester shows no current. but disconnected the wires are showing lots of juice. We've tried tracing the live wire and we have power . Help! What's next. It's been a week without my Isuzu.

It sounds like your bouncing all over with your trouble-shooting.
#1 Fuel
#2 Spark

Try spraying starting fluid in the intake while it is cranking. It it kicks off, your not getting fuel.

While cranking the engine pull a plug wire and see if spark will jump accross to the manifold. If not, no spark.

Do you have a check engine light staying on? Bad sensors can cause the same problems. Mass airflow and throttle sensors. The repair manuals show how to test these with a voltage meter.

Hey, have you figured it out? I'm having almost exactly the same problem! I've done alot of work, but nuthin'! I'm frustrated fer sure...
- Daq

the wiring to the fuel pump is probably bad. check the wiring on the harness side of the fuel pump plug. the insulation may look good but i have found 2 that the wires inside were seperated. this is a common problem on these years

I have an 88 trooper with a 4ze1 engine and have the same problem. But I have fuel and when i turn the key to the on position the fuel pump sprays. but i am not getting power or spark through the ignition coil or through the distributor does any know what is going on I am Lost need my troop this is my only vehicle. Help Please....

Have you tried the control module?

check the fuse for the fuel pump
turn the key to the on position and take a test light and check to see if electricity is making it to the fuel pump...if not work backward from there to the fuse box etc.