I have put 2 fuel pumps in my son's 02 WRX in the last year and it's dead again. The last one I put in was a walbro 255 lph pump. Is there something that could be causing these failures.

 

Thanks

Dp

Low voltage, a restriction in a fuel line, or contamination of the fuel would be my only guesses.

 

The walbros seem to have a good reputation so it sounds a little odd for that brand to fail. Any other brand besides an OEM I would not put much trust in.

does he run pump gas or use exotic fuels or additives?

 

doe he have a habit of running very low tank levels and just adding 2-3 gallons occasionally?

Test voltage at pump connector.

I concur with anything but OEM or highly touted pumps.

He only runs premium gas and no additives. He's good about keeping it filled and not running it low. We put a new one in yesterday at his place and he's going to come out this week so we can test things, line voltage, fuel pressure before and after regulator

 

We did use a walbro before, this time we went with what is supposed to be OEM but I'm not sure. It is kayoto or something. We will see what happens.

cleaning and refreshing ground connections might be worthwhile - especially if there seems to be some rust/corrosion on the car.

"Supposed to be OEM" based on research, parts store commentary, or a label on the box?

 

OE and OES are tricky marketing ploys to sound like OEM?

I have put 2 fuel pumps in my son's 02 WRX in the last year and it's dead again. The last one I put in was a walbro 255 lph pump. Is there something that could be causing these failures.

 

Thanks

Dp

 

Dirt and grit in the tank.

Or plugged filters.

 

Did you wash out the tank?

Change the filter sock?

The filter?

Every fuel pump warranty  I have ever seen requires all 3.

order your parts online through your local dealership. get instore pick up so you dont have to pay for shipping. a lot of the time the dealer part will be maybe 2 dollars more than the oem. but at least you know its the exact fit for your car. maybe swap out the fuse. check and see if too much voltage is being supplied to the fuel pump. is there a short?

Well, it quit working again. I did some trouble shooting and found 12 volts at the fuse but only 5.9 volts to the pump

I plugged it back in and it worked fine again. I don't know what to think now. Is the harness going to the pump replaceable?

Check voltage on both sides of the relay.

Not uncommon for the contacts to be bad.

Where is the relay located for the fuel pump

I think it is located in the passenger side kick panel w/a green connector.

 

You should note that some WRXs have a fuel pump controller between the relay and pump.

Its function is to control the fuel pump w/a variable duty cycle.

Not sure how that would affect your voltage readings.

diagram here

http://www.perth-wrx.com/vb/mechanicals/37207-fuel-pump-not-priming-no-start-2.html

https://forums.nasioc.com/forums/showthread.php?t=607913

 

Post #8 suggests 6-9 volts at idle is normal.

5.9 volts WA when I turned key on no start

What is WA?

 

The controllers go bad sometimes.

You may find this interesting.http://www.underhoodservice.com/subaru-pulse-width-modulated-fuel-pumps/

My bad. WA not even supposed to be in there.

Interesting read naru. Thanks for posting that.

There should be 12 volts getting to the pump when the key is first turned on but it only lasts a couple of seconds if the engine isn't running. The relay is the next thing to verify after the fuse. Then the power wire to the pump. The black/yel wire from the relay (after the relay contacts) turns to blk/red on the pump side so the connection may be between  between the those two points if the relay is okay.

Pretty sure an 02 WRX uses the pump controller.

If there is 12v on both sides of the relay contacts,I`d be checking the ground for the pump controller next.

Put your voltmeter between the ground lead (black) and battery negative and measure the voltage w/cranking.

Anything other than near 0 indicates trouble.

 

Having a look at the controller duty cycle would be very helpful if possible,

Easiest w/a scanner.

Should be 100% for a short time w/starting 33% at idle.Higher w/more throttle

Thanks for the heads-up on the controller Naru, the turbo model engine does have one. From the details given by the OP it seems there is a bad wire connection somewhere in the power circuit for the pump.