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Evogone
22-04-2009, 11:53
During the last rally we retire due to fuel pump failure (12v to the sender plug for 3 secs when priming then back to 3or4 volts but no pump) I fitted a new pump and all ok but did sound a bit weak.

Car is a clio cup car with in tank walbro pump.

Now after a day or so this now doesnt work..!! Its still getting 12v prime when switching the ignition at the plug but pump not working. But pump works when hard wired to a battery.

What about:-

Bad earth 9 (so failing under current load)
Relay (but why whould it give the 12v prime signal)
ECU not signal (again but why would it give 12v prime signal)

Need help ......

MAXIBOY
22-04-2009, 12:04
so its get 12v when switching but not when running.

have you any type of immboliser on this car.

i would also try the relay too. think its a grey item in the passenger side wing plastic engine compartment.

Evogone
22-04-2009, 12:46
so its get 12v when switching but not when running.

have you any type of immboliser on this car.

i would also try the relay too. think its a grey item in the passenger side wing plastic engine compartment.

Gets 12v at the send plug but the pump doesnt work, wire pump sender to battery direct pump goes ?

Thinking that volt meter registers 12v but when the pump pulls current it carnt (weak earthing ?)

Just lost with it..

MAXIBOY
22-04-2009, 12:59
could be the relay not allowing the current draw or as above bad earthing

i would re-earth/add earthing to it first then try a new/spare relay..

Purple
22-04-2009, 15:08
Sounds similar to what I had some time ago.
http://www.williamsclio.co.uk/forum/viewtopic.php?t=6038

northy
22-04-2009, 15:12
i had this once on my race car and it was the fuel sender mate. (on a phase 1 car)

Take the sender out of the tank if you carnt find a replacement shake it and see if it works.

Evogone
22-04-2009, 15:51
i had this once on my race car and it was the fuel sender mate. (on a phase 1 car)

Take the sender out of the tank if you carnt find a replacement shake it and see if it works.

Continutity from the plug socket on sender to the pump is OK. the pump is back in the car and wired direct to battry and pump and car runs fine.

Dont know how to check relays / and wiring earthing but the guys at the workshop have it.

Evogone
22-04-2009, 16:02
i had this once on my race car and it was the fuel sender mate. (on a phase 1 car)

Take the sender out of the tank if you carnt find a replacement shake it and see if it works.

Was it a broken connector or the wiring ?

northy
23-04-2009, 12:51
was a faulty fuel sender unit.

When mine went it stopped the fuel pump working completly.

Evogone
23-04-2009, 17:47
Seems theres a burnt fuel pump connection under the dash causing poor contact. Should be all sorted tomorrow.


:D :D :D

northy
23-04-2009, 20:35
good lad, be a good time to upgrade the wiring

Evogone
23-04-2009, 23:48
good lad, be a good time to upgrade the wiring

Agree, new engine loom done just need to do the next piece...! then the next peice then the next piece.....