Fuel Pump Power

FORSFED · 10-04-2004

I have no keyed on power back to my fuel pump. Anyone have any idea why this might be? Is there a fuel pump relay or fuse I'm missing? Otherwise I'll have to hardwire it to the ignition...

**Goat Blower** · 10-04-2004

MPI relay under the radio on 1G's. It should make a clicking noise when the key is turned on.

FORSFED · 10-04-2004

I'll have to dig for that one. I checked the MPI fuse under the hood on the positive battery terminal and that was ok. I'll have to look under the radio for the additional one.

JustROLLIN · 10-04-2004

Its a little goldish colored box. Located right under the radio on 1gs. Its bolted to the passenger side support right underneath the radio.

FORSFED · 10-04-2004

Maybe it's possible that I unplugged it at some point in time while rewiring a bunch of shit (please understand my car hasn't been running in over a year)..... I'll check it out, thanks for the info.

Alpine TSi · 10-04-2004

Is it getting ready to run? :stick: I wanna see your beast, it's been awhile.

FORSFED · 10-04-2004

It's been a VERY long while. I'm just working out the last few bugs right now. Should be good to go within a day or two......

TsiEagleTalon92 · 10-04-2004

That car is going to be the slowest thing I will ever see in my days only because im jealous!

Alpine TSi · 10-05-2004

October 10th? :stick:

**1ViciousGSX** · 10-05-2004

Are you cranking it over while checking for power? Or are you using some type of modified ecu to turn it on all the time. Our cars only power the fuel pump when the engine is cranking over.

FORSFED · 10-05-2004

I was under the impression that with the key on, the fuel pump turns on, hence a constant 12V with the ignition......

FORSFED · 10-10-2004

Ok, the way I understand the fuel pumps operation is as follows::

-Turns on for a few seconds with initial key on to pressurize the system.
-Next it shuts off.
-Turns back on while engine is cranking.

I have none of the above happening. I've traced everything back to the ecu and had no luck. The wiring is fine, the MPI relay is fine (can hear it clicking), ecu works, MPI fuse under hood is not burnt out. What does this leave??? I wired it to have keyed on power for the time being, but I'd much rather have it work with the factory wiring like it's supposed to...

A//// Guy · 10-10-2004

Do you have a logger? Try running the fuel pump with that? Otherwise try a different pump.

LightningGSX · 10-10-2004

Quote:

Originally posted by FORSFED@Oct 10 2004, 05:36 PM
Ok, the way I understand the fuel pumps operation is as follows::

-Turns on for a few seconds with initial key on to pressurize the system.
-Next it shuts off.
-Turns back on while engine is cranking.

I have none of the above happening. I've traced everything back to the ecu and had no luck. The wiring is fine, the MPI relay is fine (can hear it clicking), ecu works, MPI fuse under hood is not burnt out. What does this leave??? I wired it to have keyed on power for the time being, but I'd much rather have it work with the factory wiring like it's supposed to...

Have you tested the output from the ECU? Have you bypassed the ECU and tried actuate the relay directly?

caustad · 10-11-2004

I had a similar problem after my car sat for about a year. It turned out that the ECU fried because of the capacitors leaking while sitting, then I tried to start it and had no fuel pump power. Then when I hardwired the fuel pump like you are thinking the pump turned on but didn't shut off and the injectors sprayed wide open non-stop.

FORSFED · 10-11-2004

Eric, I don't know what wires to test. There are like 3 that connect to the MPI relay according to the diagrams in the manual. What would you suggest I test? I did try swapping a different ecu out of curiosity whether or not that had something to do with it, but I didn't get any different results.

TsiEagleTalon92 · 10-11-2004

Back when my dad had the white fireturd steve would remember something broke and the fuel pump was dead he hardwired it too but yea it would be a temp solution except you would have to turn up your idle which basically ruins the point of doing so to me.

Alpine TSi · 10-11-2004

Was that english? Complete and coherent sentences, please.

TsiEagleTalon92 · 10-11-2004

Back when my dad had the white fireturd, Steve would remember that. Something broke and the fuel pump was dead, My dad hardwired it. It would be a temp solution except you would have to turn up your idle which basically ruins the point of doing so to me.

Makes perfect sence now..