CSI elec fuel pump and pressure?

[Cornishman]

My, recently purchased and little used, csi has an electric fuel pump that runs continuously, I am surprised at this as I understand that they are run via a relay for just a few seconds when first keyed on. Does anyone know? Any guess at which relay? My Autobooks manual says take it to the dealer for fuel injection problems.

The car has starting problems when left for a while, i do not believe that it is the cold start valve because when it fires up it misses for a few seconds then is fine. If I key on and leave for two mins it then starts after a few tries. I think that it is the fuel pressure regulator that I think has a one way valve to stop bleed back. But can't find any good data. Des anyone know how to test it? I assume make a T in the fuel pipe, plumb in a low pressure gauge and run up. I was going to do this by the cold start valve pipe as it is easy access. Then key off and watch how quickly the pressure disapates? I assume the pressure is about 2 bar when running? Any suggestions where to get a suitable T piece and gauge? I think that the fuel pipe is 8 mm internal and 13 OD.

All advice welcome.
Thanks C

 

[Cornishman]

Sorry, forgot to add pictures, 1 of the electric fuel pump and one of the engine as I beleive that there are many types of FI systems fitted and I don't know which this is.

 

[mpetry912]

Adjusting CIS is kind of a black art, but there are web resources available. To check control pressure, put a guage into the fuel line between the fuel distributor and warm up regulator. The guage should have a shut off valve. There's both a cold and warm control pressure setting, in the range of 2.5 - 3.0 bar depending on temperature.

Sometimes you can tap on the WUR shaft to adjust the pressure.

Mark Petry
Bainbridge Island, WA

 

[MMercury]

My, recently purchased and little used, csi has an electric fuel pump that runs continuously, I am surprised at this as I understand that they are run via a relay for just a few seconds when first keyed on. Does anyone know? Any guess at which relay? My Autobooks manual says take it to the dealer for fuel injection problems.

The car has starting problems when left for a while, i do not believe that it is the cold start valve because when it fires up it misses for a few seconds then is fine. If I key on and leave for two mins it then starts after a few tries. I think that it is the fuel pressure regulator that I think has a one way valve to stop bleed back. But can't find any good data. Des anyone know how to test it? I assume make a T in the fuel pipe, plumb in a low pressure gauge and run up. I was going to do this by the cold start valve pipe as it is easy access. Then key off and watch how quickly the pressure disapates? I assume the pressure is about 2 bar when running? Any suggestions where to get a suitable T piece and gauge? I think that the fuel pipe is 8 mm internal and 13 OD.

All advice welcome.

For starters:

http://www.e9coupe.com/tech/dljet/dljet.html
http://www.e9-driven.com/Public/Library/BMW-E9-Manual/pages/en/13515040.html#refertoc

http://www.e9-driven.com/Public/Library/BMW-E9-Manual/pages/en/13600100.html

 

[Cornishman]

Thank you

Thank you, I wil get on a real pc and have a good lok at this at the weekend.
C

 

[John S]

csi electric fuel pump

My, recently purchased and little used, csi has an electric fuel pump that runs continuously, I am surprised at this as I understand that they are run via a relay for just a few seconds when first keyed on. Does anyone know?

The electric fuel pump on a 3.0 csi with the stock D-Jetronic setup does run continuously when the key is turned on.