Fuel pump wiring help please - urgent

Post Sat Mar 16, 2013 4:40 pm

Hiya

So ive removed my old bmw alarm, and the car no longer wants to start - I don't think its anything ive done as the car seems to have had a few wiring repairs in the past (maybe an aftermarket bruvved up alarm which has been removed)

There is the added complication of the ews system as well - I have removed the chip from the key and taped it to the sensor - so hopefully its nothing to do with that.

Where does the wire for the fuel pump come from, and which fuse is it I need to check? Can I wire it directly to make sure its nothing else / how can I bypass everything safely ?

TIA

Post Sat Mar 16, 2013 5:12 pm

Fuse 11 for the fuel pump,then on to the FPR,then green/violet to the pump.

Directly connecting the green/violet and the red/white at the FPR,s bum should make the pump run.

I had problems a few months back with my M50,would not start,fuel pump would only run when connected direct to a power source.
Tracked it to a faulty pump,then discovered that although the replacement would run,it failed to deliver fuel...this I traced to connecting the pump the wrong way round,so it blew instead of sucking...as the actress said to the bishop...

Post Sat Mar 16, 2013 6:37 pm

sorry mate - whats the fpr? and where is it located?

Post Sat Mar 16, 2013 6:43 pm

Fuel Pressure Regulator, located normally next to the Inlet Manifold

Post Sat Mar 16, 2013 6:45 pm

I thought it was, but theres no wiring there is there??

Post Sat Mar 16, 2013 6:49 pm

Ahh - I think he means fuel pump relay - that would make more sense!

Post Sat Mar 16, 2013 6:51 pm

I forgot about that!

Post Sat Mar 16, 2013 7:48 pm

ok - well I directed the wire from the relay to the pump - nothing

I had a spare pump so I tried that direct - and it buzzed to life

changed the pump, and wired it up - nothing, wired it direct and it buzzed but car didn't start

I think I have several problems with the car - the pump, the wiring, and the ews

How can I temporarily disable the ews??

Post Sat Mar 16, 2013 8:03 pm

willnz wrote:daimlerman is wrong.

The circuit starts at the pump relay. The output at the relay is from pin#87 (green/violet). This goes to fuse 11, then routes in behind the glove box, down the door post and to the rear along the sill.

Alarm fitters normally target the green/violet wire behind the glovebox.

To check if you are getting power to the rear, remove the relay, bridge pins 30-87. You should hear the pump running. If not, test power to the fuse firstly then see if there is power to the pump at the rear.

In what way?

Post Mon Mar 18, 2013 12:17 pm

ok - can someone pls confirm which way round the wires go on the fuel pump

Post Mon Mar 18, 2013 12:27 pm

With the delivery pipe removed from the fuel rail,petrol will only be delivered when the pump is wired the correct way round.With the wires reversed,the pump runs,but fails to deliver fuel.

Post Mon Mar 18, 2013 12:39 pm

yep, so what is the correct way round??

ive got the brown one on the left, and the green/purple one on the right looking at it from the cable end

Post Mon Mar 18, 2013 1:02 pm

Quaser wrote:yep, so what is the correct way round??

ive got the brown one on the left, and the green/purple one on the right looking at it from the cable end

Does the pump run?
Does the pump deliver fuel?

Post Mon Mar 18, 2013 1:07 pm

was it a factory e30 alarm? my 320i face lift car had a bmw alarm i removed car didnt start it immobilises the fuelpump green wire. lifted fuse box could see where the wire had been cut and rejoined to the alarm wiring, eg green cut then a dif colour wire connected to each side of the cut wire if that makes sence.

Post Mon Mar 18, 2013 1:32 pm

gromgsxr wrote:was it a factory e30 alarm? my 320i face lift car had a bmw alarm i removed car didnt start it immobilises the fuelpump green wire. lifted fuse box could see where the wire had been cut and rejoined to the alarm wiring, eg green cut then a dif colour wire connected to each side of the cut wire if that makes sence.

OE BMW alarm doesn't immobilise the fuel pump,if fitted as intended, and the fuel pump wire isn't green - it's green/purple.
The OE alarm does immobilise the ignition circuit (green wire), but should be connected by a plug to the factory provided socket. There should be no cut and joined wires.
The fuel pump plug isn't reversible, so you can't transpose the wires. If you want to power the pump directly as a test, then the brown wire is negative and the green/purple is positive.

Post Mon Mar 18, 2013 1:53 pm

I have looped the green wire (as per my breaker has it looped)

i took out the connectors from the plug when i was testing it, and just want to make sure i have it set correctly (the plug was missing on my breaker!)

Post Mon Mar 18, 2013 2:03 pm

It'll run (and make a noise) whichever way you connect it. It's just that fuel won't come out if it's the wrong way.

Post Mon Mar 18, 2013 2:07 pm

so which is the right way round (without taking the hose off and spurting out fuel everywhere?) pls

Post Mon Mar 18, 2013 2:51 pm

Remove delivery hose from the fuel rail,place end in a jam jar,switch on ign briefly.

Examine jam jar for fuel.

Post Mon Mar 18, 2013 3:22 pm

daimlerman wrote:Remove delivery hose from the fuel rail,place end in a jam jar,switch on ign briefly.

Examine jam jar for fuel.

Oh dear - how hard is it for someone to just tell me which way round the connectors go?

Post Mon Mar 18, 2013 3:31 pm

If you remove the fuel pump,you will see two wires connected to it,one red,one black,the brown goes to the same terminal as the black,and,strangely enough,the red matches up to the green/violet.

Much easier to check as previously described,though.

Post Mon Mar 18, 2013 3:47 pm

ok - thanks

this works out better as im not sure if the pump is kicking in!

i'll check on the spare pump!

Post Thu Mar 21, 2013 3:38 pm

used spare ews chip and now starts up a treat -

Does anyone know if the oem torch key has enough space for the chip in there?

Post Thu Mar 21, 2013 7:29 pm

Quaser wrote:used spare ews chip and now starts up a treat -

Does anyone know if the oem torch key has enough space for the chip in there?

Fairly sure there is with a little 'dremel' work.

Post Fri Mar 22, 2013 1:45 am

Mine fitted fine with the gubbins removed from within the key.

Post Fri Mar 22, 2013 8:43 am

daimlerman wrote:Mine fitted fine with the gubbins removed from within the key.

I mean with the "gubbins" still in there. Could probably get about twenty EWS chips in there with the battery, etc. removed.

Post Fri Mar 22, 2013 11:11 am

Brianmoooore wrote:
daimlerman wrote:Mine fitted fine with the gubbins removed from within the key.
I mean with the "gubbins" still in there. Could probably get about twenty EWS chips in there with the battery, etc. removed.

Having very sensitive finger tips

I have no need of an illuminated key to find the door lock in the dark!
I fitted my EWS chip where the (failed)bulb used to live.