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General => The garage => Topic started by: Blue MK2 on 27 April 2004, 11:18

Title: fuel pump doesnt stop running
Post by: Blue MK2 on 27 April 2004, 11:18
My mate has a problem with his 8v digifant GTi.

The fuel pump doesnt stop running when the ignition is on and over floods the engine, causing it to not start.

Hes tried the relay, checked fuses etc etc with no luck

anyone know the trick to solve this?


Thanx

Blue
Title: Re:fuel pump doesnt stop running
Post by: benjam_in on 27 April 2004, 11:25
is there a relay involved in that circuit?
Title: Re:fuel pump doesnt stop running
Post by: winstonb on 27 April 2004, 11:30
isnt the pump supposed to stay on?  i think the problem is at the engine end, like the injectors are fireing when they shouldnt, or the return circiut has a fault?
Title: Re:fuel pump doesnt stop running
Post by: Blue MK2 on 27 April 2004, 11:31
^ aint got a clue mate. just something he told me  ;)
Title: Re:fuel pump doesnt stop running
Post by: benjam_in on 27 April 2004, 11:35
think he means that when u turn the ignition on initally and it primes the engine for ignition that it just carries on and floods the engine?
Title: Re:fuel pump doesnt stop running
Post by: richandhazel on 27 April 2004, 11:39
I 'think' (don't know the digifant as well as the k-jet) its like the k-jet system in that respect.........the fuel pump runs continually to create a constant pressure system. Excess fuel should return to the tank.  I think winstonb is heading in the right direction in what he says. The injectors should only open when signalled to do so......no matter what the fuel pressure.
Title: Re:fuel pump doesnt stop running
Post by: richandhazel on 27 April 2004, 11:42
think he means that when u turn the ignition on initally and it primes the engine for ignition that it just carries on and floods the engine?

Even if the pump does carry on, it shouldn't flood the engine, thats why you have a return line.......once the fuel system has reached pressure, any excess should return to the tank. If it is flooding into the engine then you have a problem at the engine end.....not fuel pump.
Title: Re:fuel pump doesnt stop running
Post by: benjam_in on 27 April 2004, 11:43
sounds a bit more like it! need to get my car head on!  ::)
Title: Re:fuel pump doesnt stop running
Post by: Blue MK2 on 27 April 2004, 20:38
think he means that when u turn the ignition on initally and it primes the engine for ignition that it just carries on and floods the engine?

Even if the pump does carry on, it shouldn't flood the engine, thats why you have a return line.......once the fuel system has reached pressure, any excess should return to the tank. If it is flooding into the engine then you have a problem at the engine end.....not fuel pump.
just had a look. yes it flodds the engine. tried my relay in his car and still no luck.

when i turn my ignition on, the pump goes on for about 3 seconds but on his engine it keeps running.

just wondering if it could be something to do with the ECU?. i have one spare for sale  :P
Title: Re:fuel pump doesn't stop running
Post by: mk1 on 27 April 2004, 21:48
If the engine is flooding the injectors must be leaking or being opened. Disconnect the electrical connection to the injectors and see if it still floods. Also disconnect the ign amp as this is what triggers the coil and pulls in the pump relay, a faulty amp can trigger the coil, pump relay and injectors. Have seen a faulty ecu hold the injectors open also.
Steve.
Title: Re:fuel pump doesnt stop running
Post by: Blue MK2 on 27 April 2004, 22:03
pukka

how much do these amps and ECU's go for as i have a few spare ;)
Title: Re:fuel pump doesnt stop running
Post by: richandhazel on 28 April 2004, 11:16
Suggest you have a look on ebay see what they are going for.......
Title: Re:fuel pump doesnt stop running
Post by: Dizzie on 29 April 2004, 14:32
during my skint phase I ran a X contact relay in the fuel pump relay spot after cooking 2 fuel pump relays. when you turned the key the pump would continue unlike it should where it just primes the pressure. it never actually flooded the engine though.

god bless the K-jet ;D
Title: Re:fuel pump doesn't stop running
Post by: Blue MK2 on 01 May 2004, 20:21
If the engine is flooding the injectors must be leaking or being opened. Disconnect the electrical connection to the injectors and see if it still floods. Also disconnect the ign amp as this is what triggers the coil and pulls in the pump relay, a faulty amp can trigger the coil, pump relay and injectors. Have seen a faulty ecu hold the injectors open also.
Steve.

spot on mate with the ECU ;)

let that be a lesson

just made 60 notes ;D