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DISCUSSION => Engine + Driveline => Topic started by: visionracingdevelopments on September 02, 2009, 02:54:11 PM

Title: Fuel pump cuts out, neeeeed help!
Post by: visionracingdevelopments on September 02, 2009, 02:54:11 PM

I've come to the conclusion that the reason my car cuts out after 40 seconds of running is because the fuel pump just stops after this amount of time then fails to work after. If left for a few minutes it then runs fine again until it stops and wont start.

Could there be a problem with the relay? Can these over heat and then fail? only to work again once cool?

Would it be possible to run a new wire to the fuel pump and have it actuated by a manual switch on the interior? Or will this mess up the ECU?

Title: Fuel pump cuts out, neeeeed help!
Post by: 318lotis on September 02, 2009, 03:07:20 PM

when my fuel pump failed; symptoms:  cold starts for several weeks, then no start at all.

Title: Fuel pump cuts out, neeeeed help!
Post by: visionracingdevelopments on September 02, 2009, 03:36:08 PM

Ok.

I need to find out why mine just cuts out after 40 seconds, the about 20 seconds then doesn't work at all for a minute then repeats this process. If I can simpley rewire it for a manual switch then I will do that.

Title: Fuel pump cuts out, neeeeed help!
Post by: monty23psk on September 02, 2009, 03:39:30 PM

Pump can be going bad and it over heats. I would suspect the pump. You can always try the relay or tap it when the pump stops and see if it starts again.

Title: Fuel pump cuts out, neeeeed help!
Post by: B318M42W on September 02, 2009, 06:16:50 PM

it's your pump that's pretty much dead... easy way to find out, plug an ammeter onto it. pump power rating is about 5 amps. if you get 6.5+, on idle, then change your pump. yeah it sucks. while you're at it, check inside your fuel tank for condition and rust. if tank is full of rust, your car will eat fuel pumps very fast, and require very fequent (almost every oil change) fuel filter replacement. oh and replace the fuel filter when you change your pump. checking relay... use a jumper wire. (pump will always be on)

Title: Fuel pump cuts out, neeeeed help!
Post by: roundel318 on September 02, 2009, 09:27:48 PM

my pump would cut out for a few seconds occasionally on a road trip, it was not confidence inspiring! It acted up for about 20 minutes doing that randomly, then stopped for a few years. Then one day it took a dump and wouldnt work without banging on the fuel tank, so they replaced it and all is good :)

Title: Fuel pump cuts out, neeeeed help!
Post by: visionracingdevelopments on September 09, 2009, 01:26:39 PM

I unplugged the pump and pluged it back in and it's working for the time being.

I'll more than likely be making it redundent soon any way in favour of a boot fuel cell.

Cheers guys