e46 fuel pump

[eetaylog]

Im sat in a petrol station with my engine not turning over. After paying for my fuel, when i first tried turning it over, the starter motor kicked in but the engine wouldnt fire. After two attempts tried listening to see if i could hear the fuel pump priming, which i dont think it is.

 

Straight away i thought it must be my fuel pump gone, so i checked the fuse, and then lifted the back seat up to check the power to the pump with the multimeter that i carry around, and im getting 12V so theres definately not a problem with the power.

 

After going back and trying again though my starter motor isnt even kicking in, the lights come on but the engine doesnt even attempt to turn over!

 

I cant believe that both the fuel pump and starter motor would go at the same time, so has anyone got any pointers?? Is there a starter motor cut-out if theres no fuel getting to it or something??

 

TIA

Edited March 18, 2013 by eetaylog

[Stu]

The fuel pump won't necessarily prime every time you turn the key. It might have a timer or start event counter before it does it again.

[SteveB]

Key problem maybe - not seeing keychip? Make sure that you don't have any other keys with chips in near to the lock

[eetaylog]

The fuel pump won't necessarily prime every time you turn the key. It might have a timer or start event counter before it does it again.

 

Thanks for the quick reply stu.

 

Ive been coming back here all morning every few hours to give it another go (luckily i only work over the road), and i havent heard the fuel pump prime once. The thing thats concerning me is that the starter motor doesnt even kick in 50% of the times ive tried turning it over, just a completely dead ignition when in key pos 3 (turn over). Other times the starter will attempt to turn the engine over, but theres obviously no fuel getting to the injectors.

 

Do you think there would be a similar start event delay in the starter as well? Possibly linked to whether theres fuel in the rails or not?

 

TIA

 

Key problem maybe - not seeing keychip? Make sure that you don't have any other keys with chips in near to the lock

 

No dont think so. Engine tries turning over intermittently.

[dalelc16]

try your chip in key

[eetaylog]

try your chip in key

 

Im getting towed home in a bit. I will try my other key. Cant see it though, the starter motor works sometimes but the engine wont turn over.

[Stu]

By "wont turn over" do you mean it's not firing? Technically the starter motor turns the engine over.

 

If the starter is intermittent then.. hm.. might be security related.

 

There's a coil in the key which is excited by a ring in the ignition barrel. Those coils can break so perhaps that's it? There's a place in London who repairs the keys.

 

Have you tried a different key?

[eetaylog]

By "wont turn over" do you mean it's not firing? Technically the starter motor turns the engine over.

 

If the starter is intermittent then.. hm.. might be security related.

 

There's a coil in the key which is excited by a ring in the ignition barrel. Those coils can break so perhaps that's it? There's a place in London who repairs the keys.

 

Have you tried a different key?

 

Yes have tried a different key now but still no joy. When I say it's not turning over I mean that the starter motor tries to turn the engine over but it can't (presumably because no fuel is being pumped to the injectors by the fuel pump).

 

Normally I would have 100% said that it's a fuel pump problem because the fuel pump isn't making any noise in key pos 2, however to confuse the issue the starter motor is intermittently not starting either (in key position 3, which normally turns the engine over, it's completely dead).

 

I'm confused as to why my fuel pump would fail at the same time as my starter motor is playing up. I can't believe that they'd both independently fail at the same time!

[Stu]

It's unlikely. Much more likely is key/alarm/other_electronics

[dalelc16]

It's unlikely. Much more likely is key/alarm/other_electronics

 

 

if its todo with your alarm ect, see what the light is doing under the clock thst cwn give you a clue by the flashes ect

 

It's unlikely. Much more likely is key/alarm/other_electronics

 

 

if its todo with your alarm ect, see what the light is doing under the clock thst cwn give you a clue by the flashes ect

[Stu]

dalelc16- Did you miss the "e46" bit from the topic title?

[eetaylog]

dalelc16- Did you miss the "e46" bit from the topic title?

 

Yeah i thought that!

 

Just an update, it is looking like an immobiliser problem. Its not key related as ive tried my spare and get the same result, but the garage that are looking at it seem to think the same, so i guess its going to need recoding.

[eetaylog]

Just an update on this, all sorted now, it was the fuel pump. Boshed a new one in, let it prime a few times to get fuel to the rails and it's now all working.

 

Still a bit confused why a knackered fuel pump was causing my starter to go intermittent, but it all seems fine. :-)

[ganges]

Just an update on this, all sorted now, it was the fuel pump. Boshed a new one in, let it prime a few times to get fuel to the rails and it's now all working.

 

Still a bit confused why a knackered fuel pump was causing my starter to go intermittent, but it all seems fine. :-)

 

thanks for letting us know the problem, so many times we dont get to find out what it was or if it even got fixed, (funny i was going to ask about the update this morning), glad you are sorted

[eetaylog]

Well im back on this one, the starter is still intermittent!

 

Tried starting the car this morning, and on first attempt at turn over the starter was completely dead. On 2nd attempt though the car started just fine due to the new fuel pump now working. Theres obviously 2 seperate issues here, but im not sure whether its immobiliser related or a bad starter.