Thread: Fuel pump won't prime and fuel pump fuse problem

Im glad you got it working! Told you it was ecu related!

Well, I am puzzled that the Ecu would have ever been the issue to begin with, that Ecu was the one running on my car for a long time. Everyone that knows me locally always see me pull out the ecu out my car and straight to their car with their program.
I always run the ecu and check that fans and everything function.
There was something wrong with the wiring if it was popping fuel pumP fuses. And that is not Ecu related since the ecu signals ground outputs.
The Ecu I am sure got backfeed voltage where it should not have.
I'll check it once I recieve it.

Test #5 on page one, shows it was not related if he swapped them out and still had the same issue.

I agree with you on the ecu being back fed from another issue.. When reese and i spoke on the phone i told him it had something to do with the ecu now that he got new relays, and it was doing the same thing.. Im not doubting the ecu from the start.. Im sure it was good in the begining.

^At that time, both the original and spare relay were no good(from buzzing out on the stock ECU), so neither ECU would have worked. I switched the ECU's back and forward a couple of times, so something could have happened during my mix up. After getting the relay TJ told me to try the stock ECU again and it primed the pump. I just figured both ECU's would have been fried. The only reason the fuel fuse was popping is bc I had the air regulator connector plugged into the knock :\ at the time, so that mix up killed two relays and the fuel fuse, but not the stock ECU. I made a edit in that post just calling it a basic board. Didn't mean to post names.

EDIT: Could the grounds be bad on the stock ECU even though it finally primed the pump after the new relay install? I ask this bc I didn't get a chance to actually crank the car with it after that bc my battery was starting to die from having it the car in the 'on' position for to long. I didn't have any means of jumping it off at that moment either.



If this is the case, I most have bad luck on this deal lol. I would have been ok with the stock ECU dying, not the one I had programmed lol. Oh well.

Again, if you dont want to get another one just solder in a ground for the relay and bypass the ecu's grounding of it all together. Im sure the rest of the ecu still works and is functional to run the car properly. No need to just get rid of it especially if you fried the circut of it, not really repairable. No need to junk an ecu for that.

EDIT: Could the grounds be bad on the stock ECU even though it finally primed the pump after the new relay install? I ask this bc I didn't get a chance to actually crank the car with it after that bc my battery was starting to die from having it the car in the 'on' position for to long. I didn't have any means of jumping it off at that moment either.

^What about this just incase I decide to send this ECU off in the future? I guess I'll try boost the car off if the battery is still low to see if it turns over even if it runs rough due to the injector/MAF not being a match.

yeah, it should, Again just make sure on which side of the coil is the ground side. Dont ground the positive one. Just remove the relay and see which wire you get 12v w/ key in the on position. Then take the oposite side of the relay coil and just slit the insulation and solder in a ground while still keeping it connected to the ecu as well. Just ground to the chassis. Im pretty sure its the black w/ stripe wire but im not 100% just make sure like i said.

Again the car should still run and start even if that circuit is screwed. If it does there is no reason to junk the ecu just because of that. Nothing wrong with the pump being on all the time with the key on, you just lose your 3 second prime but instead it just stays on. So no biggie.

its getting two much of volts thats y its blowing...

Your car will turn on with a stock ecu and idle, I do it all the time on my car to test ecus out, and I am running Subaru injectors at nearly 48psi and a n60 maf. Make sure everything is working on your car.