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Matt
Matt, Mechanical Engineer
Category: BMW
Satisfied Customers: 21500
Experience:  BEng hons Mech engineering, in auto industry 22 years
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I have a 2006 BMW E46, engine size 316. The car turns over

Customer Question

I have a 2006 BMW E46, engine size 316. The car turns over but will not start. A new fuel pump and pump relay have been fitted, however, when the fuel pump is connected directly to the battery the cat starts and runs perfectly. What do we look at next?
Submitted: 3 years ago.
Category: BMW
Expert:  Matt replied 3 years ago.
Hello

if the pump and relay are new then its got to be an issue with the wiring between the relay and the pump

1st check to see what happens if you remove the relay and short out the two power supply connections ( so essentially faking a closed relay)


if the pump then runs OK you know the issue is with the ECU wire that switches the pump

if it doens't work then trace the power wire back from the relay to the pump - or just fit a new wire and cut the old one at both ends
Matt, Mechanical Engineer
Category: BMW
Satisfied Customers: 21500
Experience: BEng hons Mech engineering, in auto industry 22 years
Matt and other BMW Specialists are ready to help you
Customer: replied 3 years ago.

Tried shorting out the 2 connections, pump did not run. How do you get to the back of the relay? Have taken glove box out.

Customer: replied 3 years ago.

Sorry about the last stupid question. My husband is not sure that he changed the correct relay now that he is looking at them all behind the glove box area. What colour should it be? He changed the green one.

Expert:  Matt replied 3 years ago.
Hello Cheryl

the fuel pump relay is located behind the glove compartment and it should be no. 3 green & white in colour

Customer: replied 3 years ago.

Thank you for all your help Matt. Talking to you has got my husband to put his brain into gear. He looked at all the relays and realised he had changed the wrong one. All is well - he has just driven the car round the block!!


 


Nice photo by the way!!


 


Thanks again.


 


Cheryl

Expert:  Matt replied 3 years ago.
No problem Cheryl

and the photo was taken when I on Scrapheap challenge

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