E60 530d Boost/misfire/fluctuation problems. Help please!
Discussion
I have a couple of minor issues
1) at 70 mph whilst cruising, I get a slight misfire/boost fluctuation. I'm assuming it's not the common gearbox tc/mechatronic fault because the revs don't bounce around etc. *This is very minor, almost like when using cruise control it accelerating and decelerating very slightly to compensate for a road gradient. You struggle to see the needle change. You can feel the car slow down slightly and then resume, this is less than half a second or so. Does not occur when accelerating, purely on cruising.
2) I think the same issue as above, in second and third gear if I hold the revs at about 1700 to 2500 and accelerate slowly, I can hear the turbo spool increasing and cutting out, I. E whoosh, whoosh, *whoosh... Again like a misfire/boost issue
Both occur on very light load, I can drive the car hard and it's smooth as silk. If I'm accelerating or decelerating it doesn't occur. It is worse on cruise control. Makes no difference in manual or drive.
I've hooked up my Android phone to bluetooth adapter and used torque. App. Boost will peak at around 22psi and is around 1.5 to 2.5 cruising. I tried to see if the fluctuation affected it and want to say it did but the difference is minor so might not have.
I've recently had both thermostats done, and the DPF is now noticeably regenerating every 7 to 10 days so hopefully this isn't the issue. The car was used by a mother so I'm guessing it's done more town driving than most. Car got scanned and had a couple of glow plugs out being the only issue which I'm told doesn't affect the drive. (but oddly was told it wouldn't regenerate the dpf with two out.....)
I plan on changing the air filter, which I'm presuming when out reveals the EGR so I can clean? I've also had it suggested it's the vacuum pipes but I wasn't sure where to look for these.
Any help appreciated and pictures to aid my diy service too.
1) at 70 mph whilst cruising, I get a slight misfire/boost fluctuation. I'm assuming it's not the common gearbox tc/mechatronic fault because the revs don't bounce around etc. *This is very minor, almost like when using cruise control it accelerating and decelerating very slightly to compensate for a road gradient. You struggle to see the needle change. You can feel the car slow down slightly and then resume, this is less than half a second or so. Does not occur when accelerating, purely on cruising.
2) I think the same issue as above, in second and third gear if I hold the revs at about 1700 to 2500 and accelerate slowly, I can hear the turbo spool increasing and cutting out, I. E whoosh, whoosh, *whoosh... Again like a misfire/boost issue
Both occur on very light load, I can drive the car hard and it's smooth as silk. If I'm accelerating or decelerating it doesn't occur. It is worse on cruise control. Makes no difference in manual or drive.
I've hooked up my Android phone to bluetooth adapter and used torque. App. Boost will peak at around 22psi and is around 1.5 to 2.5 cruising. I tried to see if the fluctuation affected it and want to say it did but the difference is minor so might not have.
I've recently had both thermostats done, and the DPF is now noticeably regenerating every 7 to 10 days so hopefully this isn't the issue. The car was used by a mother so I'm guessing it's done more town driving than most. Car got scanned and had a couple of glow plugs out being the only issue which I'm told doesn't affect the drive. (but oddly was told it wouldn't regenerate the dpf with two out.....)
I plan on changing the air filter, which I'm presuming when out reveals the EGR so I can clean? I've also had it suggested it's the vacuum pipes but I wasn't sure where to look for these.
Any help appreciated and pictures to aid my diy service too.
Thanks for your reply – I’m finding it really difficult to get solid answers because most of the forums are American and the diesel lumps aren’t popular there.
Have you had your EGR replaced? Mine drove no different after having the thermostats done, apart from the DPF regeneration occasionally taking place.
I absolutely dread to think it could be the transmission – If you youtube cattle grid e60 transmission, you can see that at cruising speeds when the gearbox is worn, the needle jumps about where it cant lock in the gear. Mine doesn’t do this but it its most noticeable at the same speed.
Because it happens in lower gears though, at the same RPM, I think it is much more likely to be on the engine side. What variables are there?
Injectors – Youtubed injector fails and the engine taps etc, mine is smooth and doesn’t judder or misfire on idle.
EGR – Getting my head around how this might affect it, I don’t know if it could? Saying that it if it is gunked up, then the EGR valve might be struggling to stay open partially. I.e. opening fully or not at all?
Air filter – Checked mine, not in too bad a state and can’t see how this is an issue.
Glow plugs – I do have 2 out, but I’m told this doesn’t affect the drive once warmed up.
Transmission – If the transmission were going, I’d expect to feel more substantial movements as videos suggest.
Turbo – My turbo is quite loud, I have had turbo petrol cars before and it sounds like them (TT’s) after a remap. Not concerned about the turbo being worn as the noise is consistent with what I’m used to but is the boost being lost? Waste gate or something? I know when I replaced the recirc valve with a semi-recirc on the TT the performance was hampered.
MAF – Would it not affect all of the rev range?
Have you had your EGR replaced? Mine drove no different after having the thermostats done, apart from the DPF regeneration occasionally taking place.
I absolutely dread to think it could be the transmission – If you youtube cattle grid e60 transmission, you can see that at cruising speeds when the gearbox is worn, the needle jumps about where it cant lock in the gear. Mine doesn’t do this but it its most noticeable at the same speed.
Because it happens in lower gears though, at the same RPM, I think it is much more likely to be on the engine side. What variables are there?
Injectors – Youtubed injector fails and the engine taps etc, mine is smooth and doesn’t judder or misfire on idle.
EGR – Getting my head around how this might affect it, I don’t know if it could? Saying that it if it is gunked up, then the EGR valve might be struggling to stay open partially. I.e. opening fully or not at all?
Air filter – Checked mine, not in too bad a state and can’t see how this is an issue.
Glow plugs – I do have 2 out, but I’m told this doesn’t affect the drive once warmed up.
Transmission – If the transmission were going, I’d expect to feel more substantial movements as videos suggest.
Turbo – My turbo is quite loud, I have had turbo petrol cars before and it sounds like them (TT’s) after a remap. Not concerned about the turbo being worn as the noise is consistent with what I’m used to but is the boost being lost? Waste gate or something? I know when I replaced the recirc valve with a semi-recirc on the TT the performance was hampered.
MAF – Would it not affect all of the rev range?
Sorry for the delayed reply.
I've been speaking with a top bloke, Sean at Iridium Engineering in Southampton. Has a great rep on forums. Very knowledgable.
Withouth seeing the car, he has suggested one thing that it may well be that we haven't listed.
Variable turbo vanes clogged up with soot.
Apparently it's quite common and he said it could be causing the veins to jump suddenly/not move correctly under certain loads.
He has suggested a "revive product" that you spray into the intake which will de-coke it and clear it out to an extent.
Sounds like a highly plausible cause.
http://www.iridiumengineering.co.uk/
I've been speaking with a top bloke, Sean at Iridium Engineering in Southampton. Has a great rep on forums. Very knowledgable.
Withouth seeing the car, he has suggested one thing that it may well be that we haven't listed.
Variable turbo vanes clogged up with soot.
Apparently it's quite common and he said it could be causing the veins to jump suddenly/not move correctly under certain loads.
He has suggested a "revive product" that you spray into the intake which will de-coke it and clear it out to an extent.
Sounds like a highly plausible cause.
http://www.iridiumengineering.co.uk/
Guys
Result...I think.
Someone on the forums bought a cheap MAF sensor off ebay to fault find and it resulted in what seems to be the same issue I'm having disappearing.
Rather than go down this route I decided to unplug my MAF sensor as this is a good diagnosis start (why didn't i do this sooner?)
Anyway. My issue around town on light throttle was all the time, not intermittent . Guess what, just drove for 15 minutes trying to replicate it and it did not do it once. I could do it with my eyes blindfolded before.
I haven't got up to speed to test out the 70mph issue yet, but I'm hoping that's resolved also..
I have a theory why it only affects light throttle, the car on WOT has tons of air passing the MAF, therefore minor fluctuations in readings wouldn't really affect it... But under light throttle acceleration and cruising, changes to the readings would be much more noticeable..
I will keep you posted after a week of driving. All being well I'll buy an oem MAF sensor from Bosch.
Result...I think.
Someone on the forums bought a cheap MAF sensor off ebay to fault find and it resulted in what seems to be the same issue I'm having disappearing.
Rather than go down this route I decided to unplug my MAF sensor as this is a good diagnosis start (why didn't i do this sooner?)
Anyway. My issue around town on light throttle was all the time, not intermittent . Guess what, just drove for 15 minutes trying to replicate it and it did not do it once. I could do it with my eyes blindfolded before.
I haven't got up to speed to test out the 70mph issue yet, but I'm hoping that's resolved also..
I have a theory why it only affects light throttle, the car on WOT has tons of air passing the MAF, therefore minor fluctuations in readings wouldn't really affect it... But under light throttle acceleration and cruising, changes to the readings would be much more noticeable..
I will keep you posted after a week of driving. All being well I'll buy an oem MAF sensor from Bosch.
Drove good hour or so didn't do it once so looks positive still. Like I said I could replicate it every time.
Oem 135 quid unfortunately hence wanting to leave it unplugged a little longer before investing.
Still, damn sight cheaper than other things it could have been and at least I'll know it'll fix it.
Worth unplugging your maf to see if it fixed it too
Oem 135 quid unfortunately hence wanting to leave it unplugged a little longer before investing.
Still, damn sight cheaper than other things it could have been and at least I'll know it'll fix it.
Worth unplugging your maf to see if it fixed it too
Guys just an update on this resolution.
So I thought I had fixed it by unplugging the MAF, indicating that the MAF itself was faulty.
I was at a specialist today who I trust and showed him the symptoms, which he admitted he had not seen before. He said though he gets a lot of people phoning in saying they need a new MAF etc and it's rarely the problem.
The reason it has resolved the issue, is in his opinion, because the car will be running at default values hence has a knock on effect, for instance less boost pressure, etc etc.
anyway.....
I had the swirl flaps done today and I can confirm that this doesn't affect the problem.
However...Just sas I was leaving, I decided to unplug, and bung up the vacuum pipe operating the EGR (Which by the way, is squeaky clean on my car!!!) This has resolved the issue.
However, I don't want to get too excited as it could well be that again, unplugging the EGR has a knock on effect on something else.
But I think it's progress, and I could potentially just delete the EGR alongside the remap i'm looking to get.
So I thought I had fixed it by unplugging the MAF, indicating that the MAF itself was faulty.
I was at a specialist today who I trust and showed him the symptoms, which he admitted he had not seen before. He said though he gets a lot of people phoning in saying they need a new MAF etc and it's rarely the problem.
The reason it has resolved the issue, is in his opinion, because the car will be running at default values hence has a knock on effect, for instance less boost pressure, etc etc.
anyway.....
I had the swirl flaps done today and I can confirm that this doesn't affect the problem.
However...Just sas I was leaving, I decided to unplug, and bung up the vacuum pipe operating the EGR (Which by the way, is squeaky clean on my car!!!) This has resolved the issue.
However, I don't want to get too excited as it could well be that again, unplugging the EGR has a knock on effect on something else.
But I think it's progress, and I could potentially just delete the EGR alongside the remap i'm looking to get.
Thought I'd share an update on this, as most threads end up unanswered when the problem is fixed!
Basically I had 3 problems:
1) 70mph misfire occasionally - I finally found some info about adjusting the EGR to eliminate this problem so pointed at th EGR being potentially to blame for it all
2) Boost fluctuation at around 2000rpm on partial acceleration - Again potentially MAF/EGR related
3) Poor response - Car often wanted to downshift unecessarily for extra revs, and on accelerator being pressed there was lag.
Another symptom as a result of this strange behaviour was the shifts being a bit firm.
So I unplugged the MAF and it fixed the symptoms, but as it runs in default mode wasn't necessarily the cause.
I then unplugged the EGR and again fixed the symptoms but may not have been the issue.
I'd had the swirl flaps removed so knew they weren't to blame.
Sooo....
Today, I had the remap done - accompanied with an EGR delete - And, it's fixed it. Basically the EGR is to blame but I couldn't be certain without the car having an engine fault removed.
Smooth acceleration, better shifts, responsivenss is epic (obviously even better with the remap). I will add my EGR was spotless, but it's the pressure converter I believe is to blame.
Couldn't be happier, what a result as it only cost me the remap!
Basically I had 3 problems:
1) 70mph misfire occasionally - I finally found some info about adjusting the EGR to eliminate this problem so pointed at th EGR being potentially to blame for it all
2) Boost fluctuation at around 2000rpm on partial acceleration - Again potentially MAF/EGR related
3) Poor response - Car often wanted to downshift unecessarily for extra revs, and on accelerator being pressed there was lag.
Another symptom as a result of this strange behaviour was the shifts being a bit firm.
So I unplugged the MAF and it fixed the symptoms, but as it runs in default mode wasn't necessarily the cause.
I then unplugged the EGR and again fixed the symptoms but may not have been the issue.
I'd had the swirl flaps removed so knew they weren't to blame.
Sooo....
Today, I had the remap done - accompanied with an EGR delete - And, it's fixed it. Basically the EGR is to blame but I couldn't be certain without the car having an engine fault removed.
Smooth acceleration, better shifts, responsivenss is epic (obviously even better with the remap). I will add my EGR was spotless, but it's the pressure converter I believe is to blame.
Couldn't be happier, what a result as it only cost me the remap!
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