Fuel pump woes

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BPhil

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Hi All, Have a 3.0 CSI. Recently the car stopped, like it had run out of fuel. Presumed it was a failing pump but one brand new pump later, the car starts but won't run. A shot of "starter" and it will run for perhaps 10 seconds then die. From a previous thread I saw a recommendation to test the "run" circuit for the fuel pump ?, (switch from the AFM ?) but can't find the thread again. Can anyone tell me how to test, if this is the problem ? Please keep it simple for me.
Thanks again
Brett Phillips
 
Unless you did an engine swap, there is no afm on a csi.
There is a fuel pump relay under the pass. rear seat.
Turn the key on and you should hear it click.
It turns on and powers up the pump for about 1 second whenever you turn the key on so that the fuel pressure is high enough to operate with fuel injectors.
disconnect the fuel line at the front of the fuel rail and stick it in a plastic jug.
Spray the starter in and fire up the car like before- do you have fuel pumping into the jug as long as the enginer is running?
 
I tested that before, the relay clicks and the pump buzzes for a second. When I disconnected the line from the rail, a spray of fuel when I first released the line, but no significant flow into the jug on cranking ?
 
Jumper the positive pin of the fuel pump or the fuel pump relay with a 15 amp fused wire direct to battery.

Try it again!
 
BPhil said:
I tested that before, the relay clicks and the pump buzzes for a second. When I disconnected the line from the rail, a spray of fuel when I first released the line, but no significant flow into the jug on cranking ?
Click to expand...

So you do get an initial pressure up? You can hear the pump buzz as well as the relay click? But no fuel during cranking, correct?

Odd, mine had the relay pick up but no fuel from the fuel rail during cranking. And yes, the pump was bad.

This might help

http://www.e9coupe.com/forum/showthread.php?t=12495
 
I ran a jumper from the battery to the pump (it made all the right noises)and cranked the engine but still no start ! I disconnected fuel line and ran the pump again for 20 seconds it pumped about 400ml. Not sure where that leaves me. Should I be bleeding the system somehow to expel any air in the filter and rail ? This was all done in a bit of a hurry, so I'll try again this afternoon, but any other ideas will be welcome. Thanks Brett
 
Your pump is fine.
Now time to check for spark. Get a spare plug
and stick it in #5 plug wire and lay on valve cover.
Crank it and tell us if you have spark.
 
Just had another go at starting without getting in the car. It idled (roughly) for perhaps 10 seconds but died as soon as i pushed the acelerator. Normally I give the throttle a couple of pumps before cranking. Not sure if this means anything ?
Thanks again for any suggestions.
 
no need to pump the gas pedal on a fuel injected car. :]]

What did the spark look like when you tested it?
 
test the resistance between the negative post of your battery and your valve cover.
when you do it- have some one depress the gas pedal
[all with the engine off]
 
I may have found the problem. A mate loaned me a gauge to test the fuel pressure and I note that it's around .8 bar. I believe it should be around 2 - 2.5 ? A faulty pump ?
 
Did you test at the fuel rail at the front of the engine?
 
Check for vacuum leaks. Sounds like a hose could be loose, cracked or have a hole in it and it is trying to start but then runs lean and stops. Check large hose from throttle body to make sure it is on manifold tightly.
 
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