1989 Isuzu Trooper 2.8 eng - Won't start

[nidansan]

1989 Isuzu Trooper 2.8 engine - Won't start.

I have spark! If I feed gas, it will try to start immediately. Checked all fuses, fuse links. Removed gas tank, bypassed fuel pump and it works. The fuel pump does not turn on without bypassing it. I did noticed that the check engine light does not go on when I turn the ignition (yes! the bulb is OK). I cleaned all ground connections and tested them with a volt meter.

I don't know if there is a cut off switch or any other switch that keeps the pump from turning on. Recently I have done the following: Changed fuel pump relays with others that I have, did the same for the master relay.

My next option is to bypass the relays; I need more info in order to do it. I also changed the ECM (computer) for another, also changed the chip to make sure that the chip is not the problem.

I don't have good wiring diagrams or a good shop manual, I have a Mitchell CD, but the drawings are kinder like and not clear.

If anyone has had a similar problem, I would like to hear from you!


Any help will be greatly appreciated! I am going

Thanks!

[nidansan]

FOUND THE PROBLEM!!! ONE Of the FUSE Links Was BAD. I took my volt meter and tested all of the fuse links AGAIN! Noticed that one of them was not passing current constantly. Took it off and used my Ohm meter and wala, it is BAD... Replaced it and the Check engine light came on!

[nidansan]

FOUND THE PROBLEM!!! ONE Of the FUSE Links Was BAD. I took my volt meter and tested all of the fuse links AGAIN! Noticed that one of them was not passing current consistantly. Took it off and used my Ohm meter and wala, it is BAD... Replaced it and the Check engine light came on!