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Help!!!
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- Member
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- Location: Near Carmarthen
Help!!!
Hi all, my 05 m54 2.5i is currently on a sorn and cannot be driven as cuts out upon acceleration. The car appears to go into some kind of safe mode, with the engine revs pulsating regularly until its turned off and on again. You can't drive it whilst it does this. I cannot replicate the fault whilst being stationary and revving as the car has to be moving. Inpa shows nothing in the faults, but oddly my c110 will regularly show lean codes (I'm not sure if this is related). So far in an effort to find the cause of the lean codes iv inspected the air intake pipe (was new a few years back), cleaned the maf, replaced the disa oring (vain was also previously replaced), and replaced the ccv pipes etc. Nothing is making a difference. I haven't smoked tested the system as yet. I'm pulling my hair out (if I had any)!. I did wonder if the maf is gone on, but am unsure how to test this?
Hope that makes sense and all suggestions greatly received.
Hope that makes sense and all suggestions greatly received.
2005 e85 z4, 2.5
- enuff_zed
- Lifer
- Posts: 14930
- Joined: Wed Oct 26, 2016 11:05 am
- Location: Attleborough, Norfolk
Help!!!
So when you accelerate it needs more fuel and sounds like it’s not getting it. Therefore runs badly and lean codes. Is the fuel pump delivering enough? Is the fuel rail pressure ok? Definitely sounds an issue with fuel delivery or the control of that.
Maf, injectors, DME, all worth looking into.
Maf, injectors, DME, all worth looking into.
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Help!!!
I was about to say fuel delivery related too in regards to the low pressure fuel pump. Sounds like the G force of accelerating is causing fuel starvation.enuff_zed wrote: ↑Wed Feb 08, 2023 3:21 pm So when you accelerate it needs more fuel and sounds like it’s not getting it. Therefore runs badly and lean codes. Is the fuel pump delivering enough? Is the fuel rail pressure ok? Definitely sounds an issue with fuel delivery or the control of that.
Maf, injectors, DME, all worth looking into.
Sapphire Black E86 LN56 ZKJ Purchased Jan 2021 - Sold June 2022
Bilstein B12 Pro Kit
Eisenmann Quad Exhaust
BMW Z4M Rear Bumper
Bilstein B12 Pro Kit
Eisenmann Quad Exhaust
BMW Z4M Rear Bumper
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- Posts: 325
- Joined: Tue Aug 30, 2016 5:37 pm
- Location: Near Carmarthen
Help!!!
How do I test the fuel pump etc?enuff_zed wrote: ↑Wed Feb 08, 2023 3:21 pm So when you accelerate it needs more fuel and sounds like it’s not getting it. Therefore runs badly and lean codes. Is the fuel pump delivering enough? Is the fuel rail pressure ok? Definitely sounds an issue with fuel delivery or the control of that.
Maf, injectors, DME, all worth looking into.
2005 e85 z4, 2.5
- enuff_zed
- Lifer
- Posts: 14930
- Joined: Wed Oct 26, 2016 11:05 am
- Location: Attleborough, Norfolk
Help!!!
I'll be honest................. not sure. But I reckon a garage would be able to measure the pressure in the fuel rail for you.andystone wrote: ↑Wed Feb 08, 2023 3:48 pmHow do I test the fuel pump etc?enuff_zed wrote: ↑Wed Feb 08, 2023 3:21 pm So when you accelerate it needs more fuel and sounds like it’s not getting it. Therefore runs badly and lean codes. Is the fuel pump delivering enough? Is the fuel rail pressure ok? Definitely sounds an issue with fuel delivery or the control of that.
Maf, injectors, DME, all worth looking into.
However, for simplicity's sake I think I would be looking to at least borrow another MAF first to see if that is the issue.
As BumpyZ4 says, you could disconnect it as it will then run on a default set of values which should at least tell you if that is your fault or not.
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Help!!!
Cheers, much appreciated. I see that inpa will also test the fuel pump, there is a YouTube video I've just seen, so I'll be having a play with inpa again.enuff_zed wrote: ↑Wed Feb 08, 2023 4:00 pmI'll be honest................. not sure. But I reckon a garage would be able to measure the pressure in the fuel rail for you.andystone wrote: ↑Wed Feb 08, 2023 3:48 pmHow do I test the fuel pump etc?enuff_zed wrote: ↑Wed Feb 08, 2023 3:21 pm So when you accelerate it needs more fuel and sounds like it’s not getting it. Therefore runs badly and lean codes. Is the fuel pump delivering enough? Is the fuel rail pressure ok? Definitely sounds an issue with fuel delivery or the control of that.
Maf, injectors, DME, all worth looking into.
However, for simplicity's sake I think I would be looking to at least borrow another MAF first to see if that is the issue.
As BumpyZ4 says, you could disconnect it as it will then run on a default set of values which should at least tell you if that is your fault or not.
2005 e85 z4, 2.5
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Help!!!
Well, I unplugged the maf and absolutely nothing happened to the running of the engine. Is the maf dead? Also is the 'secondary air mass' the maf? Or something completely different (it doesn't move at all on the inpa).
2005 e85 z4, 2.5
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- Posts: 325
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Help!!!
How noisy should the fuel pump be? A gentle humming with some odd groaning when I turn it on and off using inpa.enuff_zed wrote: ↑Wed Feb 08, 2023 3:21 pm So when you accelerate it needs more fuel and sounds like it’s not getting it. Therefore runs badly and lean codes. Is the fuel pump delivering enough? Is the fuel rail pressure ok? Definitely sounds an issue with fuel delivery or the control of that.
Maf, injectors, DME, all worth looking into.
2005 e85 z4, 2.5
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- Member
- Posts: 325
- Joined: Tue Aug 30, 2016 5:37 pm
- Location: Near Carmarthen