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-   -   Fuel pump not Priming. No start. (http://www.perth-wrx.com/vb/mechanicals/37207-fuel-pump-not-priming-no-start.html)

Bridantay 21-09-2010 08:45 PM

I had the same issue today, friggin fuel pump wont prime. I can also hear the relay kicking in but nothing happening. So I feel your pain, had to work from home cause of it. The difference is I leave the car go for a few hours and it will always start later. My WRX is a 97 and I dont have a Brandt, I have an after market alarm. I have a feeling its the fuel pump for me thou.... Sorry your issue isnt as straight forward

VETTETOREX 21-09-2010 09:02 PM

Good luck with it Bridanty.

What surprised me today when it fired up is the blue relay got really hot so maybe all of this could be a result of a dying pump working too hard. But for all I know the heat could be normal considering they are metal relays and I assume a fuel pumps draws some Amps. Hopefully she'll prime again sometime then I can check for 12v at the harness when it does and see if I'm doing it right.

Anyway searching the internet it seems many, many people have had this problem and it could be due to many things really because most never come back and say what fixed there problem.

Okibi 21-09-2010 09:46 PM

Sounds like the relay is dodgy to me.

VETTETOREX 21-09-2010 11:31 PM

That's what I hoped at first but it can't be the relays. Tested both relays by applying 12V to the coil pins and they both click and the other 2 terminals have continuity.

Then when plugged in the car and key on, both relays test fine with 12V to the coil pins and 12V through the other pins (On blue harness). With the relay unplugged the Harness tests fine too.

I haven't had time to check but I think the pink plug may be the main relay as when i was checking earlier it had a hot 12V even with the key off. So with that unplugged the car shouldn't crank right? Then with Key to start one of the other pins should get 12v to energize the relays coil and click the switch inside to crank.

Rossco said that the brant will activate the Fuel pump relay. What I need to know for 100% is... Is the blue harness relay definately the fuel pump relay(pretty sure it is) and what is between that and the fuel pump harness. I have 12v coming out of that relay but nothing at the pump harness so its either a broken connection or there is another component between the fuel pump relay and the fuel pump. (Hopefully not the Brant)

If there isn't and the blue harness is 100% the fuel relay which is outputting 12V, and there is nothing but wires/plugs between the fuel pump relay and the Fuel pump. It should just be a stuffed wire, plug between them, possibly caused by a dying Fuel pump drawing too many amps(hence the relay getting hot)

Update: I have a 1998 wiring diagram and the fuel pump relay goes to the fuel pump. I also have a 2002 wiring diagram and the fuel pump relay goes to a Fuel pump controller which then goes to the fuel pump. This doesn't help me much as I have no idea if my car (MY'00) has one or not.

VETTETOREX 21-09-2010 11:51 PM

These may not be relevant but...If blue relay IS fuel pump relay and it's pushing 12V then this diagram shows a straight link to the fuel pump which would mean I have a bad connection or melted plug or something from a dying fuel pump.

1998 WRX
[IMG]http://i744.photobucket.com/albums/xx81/Visonhead/1998.jpg[/IMG]

If the car has a fuel pump controller then things become more complicated.

2002 WRX
[IMG]http://i744.photobucket.com/albums/xx81/Visonhead/2002.jpg[/IMG]\

Neither of these may be relevant as I have no info on an MY00.

Can anyone guide me in the right direction or am I barking up the wrong tree?

Rossco 22-09-2010 12:48 AM

Fuel pump control unit is Bugeye onwards.

You should have a direct link from the relay to the fuel pump on 99-00 Gc8.

If the relay is heating up you have a short or the f/p is pulls lots of current because its seizing.

VETTETOREX 22-09-2010 11:48 AM

Here's what happened. Theses cars are crazy with the amount of bunched up tangled wires under the dash.

I mentioned a few times I wasn't sure what the blue and pink relays were for and did ask for confirmation several times that the blue one was the fuel pump relay (which I never got)

When testing for an open circuit from the fuel pump back and pulling the wrapping apart here and there I finally traced the positive all the way up the dash (right up there where I couldn't see before until I wrestled with another bunch of thick tightly wound wires), to another set of identical looking relays- one with a green plug and a brown main relay in between.

So hey I finally found my relay and no voltage. Traced the wire that energizes the fuel pump relay which has been spliced to a wire from the Brant module.

The Brant was cable tied up loosely and had the date March 02 on the side. So it must of been replaced once already.

I opened her up and gave the relay joints a solder but still no voltage on the pin which goes to the Fuel pump relay.

As Rossco said before the relay must be stuffed so this is what I'm gonna do.

I'm gonna leech 12V of the relay which is outputing 12v like this.

I already jumped it and the Fuel pump whirred to life for 2 seconds.

[IMG]http://i744.photobucket.com/albums/xx81/Visonhead/070620090401.jpg[/IMG]

I haven't tried to start it yet as I don't know If it'll break anything.

Is this a good Idea?

What exactly are the other 2 relays for. The one on the left has no voltage either.

I'm sure this is a cheap fix for my problem till I can piss the brant off all together.

How does Brant stay in business when everybody always has problems with them.

Thanks for all the help.

VETTETOREX 22-09-2010 12:08 PM

YAYYYY!!! IT"S ALIVE!!!!

I can't see any detrimental effect of leaving it like this.

Stupid Brant. Gone from a 3 point immobilizer to a 2 point.

I assume the other 2 relays are starter and ignition.

Thanks for all the help. I barking up the wrong tree.:icon_salu

Rossco 22-09-2010 01:07 PM

Just be aware that the on board brant relay carries the load of the f/p relay not the modules pcb....Be carefull as you may burn the track on the pcb.

you should be able to source a pcb mounted relay through jaycar or similar.

VETTETOREX 22-09-2010 02:11 PM

That makes total sense.

Would the fuel pump relay load not be much at all(I hope), and a large current draw would be through the actual FP relay switch inside.

I'm guessing the Brant relay would just energize the coil inside the FP Relay to close the switch (not taking too much current) and the major current draw would be through the relay switch mechanism. Such skinny wires to the relay.

Damn I thought I had a win. Now I ponder.

I'll see how it goes and keep an eye on it. Maybe try and get another relay. If I possibly burn a track on the PCB and car doesn't catch on fire I can always just solder a wire from point to point. Pretty Redneck.

I wish i knew how to totally bypass the Brant.


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