Hey guys, Ive been away for a while.

Any ways,

My Trooper died last week while driving. I check the fuel pressure and had nothing. I replaced the fuel pump and it ran flawlessly for 5 days. Then I went to get in the car, it started, began to sputter, then died. I checked the fuel pressure again, it had nothing. I checked the fuse, it was good. I swapped the fuel pump relay with the a/c relay (same relay) to see if it was bad. This did nothing as well. I began to curse at auto zone for selling me a fuel pump that died in a week. Last night I replaced the pump again.

Here is the problem.......

I benched tested the pump I pulled out, it was working. I turned the key to the new pump I just put in...nothing. It was not spinning up. I began to check all connections, they were fine. I replaced the fuel pump fuse anyway. It fired up. I thought hmmmm, ok that must have been it. I drove it around the block, ran fine. Then when I got back, I started it again. It began to sputter and almost die, then it regained its integrity and fired up fully. I though, it must be a bad negative battery connection! It had been loose and iffy. I refitted the post, and the car fired up fine 4 times in a row. I went to bed.


Got up this morning, went out to the car and nothing. Wont start. I listened, and the fuel pump in snot kicking on at all once again. Im confused!

New pump, I know it works, replaced fuse, not blown. swapped relay, so thats not it. WTF am I missing? Anyone know what could cause it to come on and off periodically? This if our only vehicle right now, so I need to get this figured out.
thanks!

If an Isuzu Trooper is the same as a Vauxhall/Opel Frontera, then my friend had the selfsame problem. I believe that was caused by the Alarm system being disabled by low battery voltage. Discovered the solution by chance unhooked the battery, to replace it with a new one, and it worked straight off first time, and never a problem since. I KNOW it had an Isuzu engine in it.
Nick
Edit to add: disconecting the battery, and replacing it with a fully-charged new one, reset the ECM and alarm/disabling system.

[This message has been edited by fierofetish (edited 07-13-2010).]