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Lazy, Jerky, Horrible Throttle

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Sam1977
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Lazy, Jerky, Horrible Throttle

Post by Sam1977 » Sat Sep 02, 2017 5:48 pm

Thanks for the input. Presumably now you disconnected MAF you have CEL on - can that simply be reset by standard OBDII scan tools? I have a few - Foxwell, a specific BMW one that I bought on Amazon and another cheapo one. I am tempted to try and disconnect the MAF as you have but only want to do that if I know I can reset the CEL. Can you confirm that?

The other possibilities - TPS/ICV I don't really want to get into doing myself - I could do it, and have the tools and know-how but I just don't have the time to spend doing it.

However the MAF is a 2 second job - just worried about the reset! I'd appreciate your advice on that as the appointment at BMW has been put back to Tuesday so I have time: keep me posted on yours and I will do likewise, see if we can get these cars tip top!!

All the best
Sam.
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Porsche 911 Turbo S / Boxster S
BMW E60 M5 / E38 740i / E46 320d / E36 316i / E46 330Ci (Time Attack car)
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AndyBeech
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Lazy, Jerky, Horrible Throttle

Post by AndyBeech » Sat Sep 02, 2017 7:23 pm

ImageThe EML for MAF will turn itself off straight away once plugged back in, or at worst after a few runs. Trouble with taking out the MAF for diagnosis is the car will run on its Alpha-N map which disregards certain readings from other sensors so won't neccasirly mean the MAF is the fault if it goes away if you get my drift.
Worth a shot though, I've changed MAF before and it didn't solve the rev dip issue I had. If you change the MAF you should also delete the adaptations in the DME so it can relearn its running values otherwise it'll just use the ones it had prior to the change and will take a while to readapt itself to any change of parts.
TPS issues won't always trigger the EML light unless it's really knackered, if it's a bit 'lazy' the car may just work around it rather than throw a light, in my experience anyway....Lots of people have changed the TPS sensor to good affect with no EML light showing.

Also consider VANOS issues would contribute to poor idle and reduced low down power output.

Edit: getting to the TPS/ICV is an easy job, can be done in about an hour or so, once you've done it once it's worth doing as you can carb clean all the butterfly valves on the throttle bodies, ICV, actuator and assosciated springs. May or may not help but can't hurt.
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Sam1977
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Lazy, Jerky, Horrible Throttle

Post by Sam1977 » Sat Sep 02, 2017 8:21 pm

Thanks Andy - I was put off on the TPS/ICV thing based on an article from Pelican Parts that said 5 hours!! I must admit having had the whole inlet manifold and throttle body out more than once on my 330 Time Attack car in much less time I did scratch my head at that!

Okay I understand how a MAF works and interacts with DME so your caveat aside I will give that a bash and see.

To clarify on my issue which seems slightly different from that of the OP, my idle is fine, my acceleration above 1000rpm is fine, my issue is a rev dip on light throttle which makes it easy to stall and it is completely consistent/persistent and stabbing the throttle in neutral I have the rev dip and a slight cough before it revs clean over 1000. Based on that (and I don't want to hijack the OP's thread here ...) whats your advice?

Thanks all
Sam.
BMW Z4M INTERLAGOS BLUE
Other tin:
Porsche 911 Turbo S / Boxster S
BMW E60 M5 / E38 740i / E46 320d / E36 316i / E46 330Ci (Time Attack car)
Mercedes SL500
Hyundai Accent Copa (Andalucia Cup) x3
Audi A6 Avant x2
Nissan Navara
Fiat Punto Sporting

nichollsz4
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Lazy, Jerky, Horrible Throttle

Post by nichollsz4 » Sun Sep 03, 2017 12:36 pm

Just to add to this,

My car feels absolutely fine performance wise. It idles fine and doesn't ever feel like it's going to stall. It's just got an awful throttle response, which, when pottering around, is just awful drive.

With the MAF sensor disconnected, EML came on and nothing else. No change in how the car drives. I've plugged it back in and waiting for the light to go off. Will let you know how I get on.

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Lazy, Jerky, Horrible Throttle

Post by nichollsz4 » Sun Sep 03, 2017 4:15 pm

EML light does go off once plugged back in. Probably takes up to 30 miles before the light goes off.

Throughout the time I've had the MAF unplugged I saw no difference at all. I'll likely replace this first, then the TPS. I have access to diagnostic tools so willl reset the adaptations once replaced.

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Post by Sam1977 » Sun Sep 03, 2017 5:12 pm

nichollsz4 wrote: Sun Sep 03, 2017 4:15 pm EML light does go off once plugged back in. Probably takes up to 30 miles before the light goes off.

Throughout the time I've had the MAF unplugged I saw no difference at all. I'll likely replace this first, then the TPS. I have access to diagnostic tools so willl reset the adaptations once replaced.
Thanks - sound like its not the MAF though - how much is a new one for this model?
BMW Z4M INTERLAGOS BLUE
Other tin:
Porsche 911 Turbo S / Boxster S
BMW E60 M5 / E38 740i / E46 320d / E36 316i / E46 330Ci (Time Attack car)
Mercedes SL500
Hyundai Accent Copa (Andalucia Cup) x3
Audi A6 Avant x2
Nissan Navara
Fiat Punto Sporting

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Post by mad4slalom » Sun Sep 03, 2017 6:10 pm

Hi, does yours do this on every gearshift or just on occasion? Sport button on or off,? These can suffer from awful kangarooing on occasion if youcome off the throttle say into a mini roundabout or junction in second gear and then come back on the throttle, it can be quite dramatic, and am coninced it is the fly by wire throttle as never had it in my z3m with a mechanical throttle cable. Seems to be when you have sport button on too. Other thing i have noticed , you mention lazy throttle response, I have always found throttle slow to pick up when blipped to rev match. I will try the throttle reset too as havent done that for a couple of years. :driving:

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Post by VRSteve » Sun Sep 03, 2017 6:43 pm

srhutch wrote: Fri Sep 01, 2017 11:30 pm
Sam1977 wrote: Thu Aug 31, 2017 3:31 pm Hi my car is going to BMW Carteya in Algeciras on Monday as I have a slight problem at idle revs when I go to drive off the revs dip slightly when I apply light throttle making it very easy to stall. These cars seem to suffer from an issue that doesn't affect the equivalent M3. I have no CEL and no codes so its not clear enough to me to be able to diagnose adequately. Loads of threads around on it but nothing conclusive anywhere unfortunately so rather than follow the common parts replacement and cleaning and see if it works I am just going to take it to BMW and tell them to sort it out!! I would imagine the possibilities are ICV, TPS, lambda sensor, fuel filter, vacuum leak or something like that. Going to have a few blemishes on paint sorted out at the same time. I'll let you know what they do to mine.

Just to try and relate my issue back to yours, its not identical - mine only has an issue with a rev dip from idle, beyond 1000rpm I have no hesitation or any other issue. But that's not to say mine isn't an issue that could progress into something worse if not resolved.
Is this under warranty?
Isn't this a common problem resolved by a new ICV???
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Sam1977
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Post by Sam1977 » Sun Sep 03, 2017 9:04 pm

mad4slalom wrote: Sun Sep 03, 2017 6:10 pm Hi, does yours do this on every gearshift or just on occasion? Sport button on or off,? These can suffer from awful kangarooing on occasion if youcome off the throttle say into a mini roundabout or junction in second gear and then come back on the throttle, it can be quite dramatic, and am coninced it is the fly by wire throttle as never had it in my z3m with a mechanical throttle cable. Seems to be when you have sport button on too. Other thing i have noticed , you mention lazy throttle response, I have always found throttle slow to pick up when blipped to rev match. I will try the throttle reset too as havent done that for a couple of years. :driving:
Hi not sure which one you are asking - for me my rev-drop issue on pulling away with light throttle or a drop/cough when stabbing the throttle at idle happens whether sport button is or or off. Have tried reset - I initially thought it worked because the car was cold and so the revs settled back at about 1000rpm but once warm and they are at operating idle thats when I experience the problem. My issues are basically sub-1000rpm
BMW Z4M INTERLAGOS BLUE
Other tin:
Porsche 911 Turbo S / Boxster S
BMW E60 M5 / E38 740i / E46 320d / E36 316i / E46 330Ci (Time Attack car)
Mercedes SL500
Hyundai Accent Copa (Andalucia Cup) x3
Audi A6 Avant x2
Nissan Navara
Fiat Punto Sporting

Sam1977
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Post by Sam1977 » Sun Sep 03, 2017 9:12 pm

VRSteve wrote: Sun Sep 03, 2017 6:43 pm
srhutch wrote: Fri Sep 01, 2017 11:30 pm
Sam1977 wrote: Thu Aug 31, 2017 3:31 pm Hi my car is going to BMW Carteya in Algeciras on Monday as I have a slight problem at idle revs when I go to drive off the revs dip slightly when I apply light throttle making it very easy to stall. These cars seem to suffer from an issue that doesn't affect the equivalent M3. I have no CEL and no codes so its not clear enough to me to be able to diagnose adequately. Loads of threads around on it but nothing conclusive anywhere unfortunately so rather than follow the common parts replacement and cleaning and see if it works I am just going to take it to BMW and tell them to sort it out!! I would imagine the possibilities are ICV, TPS, lambda sensor, fuel filter, vacuum leak or something like that. Going to have a few blemishes on paint sorted out at the same time. I'll let you know what they do to mine.

Just to try and relate my issue back to yours, its not identical - mine only has an issue with a rev dip from idle, beyond 1000rpm I have no hesitation or any other issue. But that's not to say mine isn't an issue that could progress into something worse if not resolved.
Is this under warranty?
Isn't this a common problem resolved by a new ICV???
I suspect ICV as the most likely culprit in this case so yes I hope this is the issue and will be resolved by ICV replacement - I have suggested already to BMW that this might be the cause ahead of taking it there but also made clear it could be another issue and that they should diagnose it. The issue is so consistent with the rev drop that I can easily demonstrate to them - its not an intermittent problem. They are pretty good at Carteya - have used them for years. They don't do anything without consulting first. I am not massively stressed by the whole thing, and after a lot of research it seems this "common problem" is probably actually a set issues that are not in fact all common due to the totally different characteristics of each - the only things that really get my a hole squeaking are engine internals!!
BMW Z4M INTERLAGOS BLUE
Other tin:
Porsche 911 Turbo S / Boxster S
BMW E60 M5 / E38 740i / E46 320d / E36 316i / E46 330Ci (Time Attack car)
Mercedes SL500
Hyundai Accent Copa (Andalucia Cup) x3
Audi A6 Avant x2
Nissan Navara
Fiat Punto Sporting

D4dawg

Lazy, Jerky, Horrible Throttle

Post by D4dawg » Sun Sep 03, 2017 9:28 pm

Would the idle control valve have any affect in this matter ?

As if it's lumpy and coupled with lazy or non responsive throttle this can't help ?

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Post by Sam1977 » Sun Sep 03, 2017 9:41 pm

D4dawg wrote: Sun Sep 03, 2017 9:28 pm Would the idle control valve have any affect in this matter ?

As if it's lumpy and coupled with lazy or non responsive throttle this can't help ?
Which car are you referring to? There's now three in this thread. Suggest quoting the last message you are replying to for clarity
BMW Z4M INTERLAGOS BLUE
Other tin:
Porsche 911 Turbo S / Boxster S
BMW E60 M5 / E38 740i / E46 320d / E36 316i / E46 330Ci (Time Attack car)
Mercedes SL500
Hyundai Accent Copa (Andalucia Cup) x3
Audi A6 Avant x2
Nissan Navara
Fiat Punto Sporting

D4dawg

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Post by D4dawg » Sun Sep 03, 2017 10:34 pm

Sam1977 wrote: Sun Sep 03, 2017 9:41 pm
D4dawg wrote: Sun Sep 03, 2017 9:28 pm Would the idle control valve have any affect in this matter ?

As if it's lumpy and coupled with lazy or non responsive throttle this can't help ?
Which car are you referring to? There's now three in this thread. Suggest quoting the last message you are replying to for clarity
Bit cheeky coming from you 36th post
As its the post headed I'll always refer to that not others in thread as it's the main question not subsequent issues

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AndyBeech
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Post by AndyBeech » Mon Sep 04, 2017 1:57 pm

Sam1977 wrote: Sun Sep 03, 2017 9:12 pm
VRSteve wrote: Sun Sep 03, 2017 6:43 pm
srhutch wrote: Fri Sep 01, 2017 11:30 pm

Is this under warranty?
Isn't this a common problem resolved by a new ICV???
I suspect ICV as the most likely culprit in this case so yes I hope this is the issue and will be resolved by ICV replacement - I have suggested already to BMW that this might be the cause ahead of taking it there but also made clear it could be another issue and that they should diagnose it. The issue is so consistent with the rev drop that I can easily demonstrate to them - its not an intermittent problem. They are pretty good at Carteya - have used them for years. They don't do anything without consulting first. I am not massively stressed by the whole thing, and after a lot of research it seems this "common problem" is probably actually a set issues that are not in fact all common due to the totally different characteristics of each - the only things that really get my a hole squeaking are engine internals!!
I replaced the ICV on mine, waste of money IMO if it's coming out you're own pocket, under warranty though is fair enough. If you look at it, it's just a simple valve that open and closes...it kinda either works or it doesn't, nothing complicated to it. The only thing worth doing with it is spraying a load of carb cleaner in there to get rid of carbon build up as that *could* make it a bit sticky potentially. That's about it. I've got my old one in the garage that looks like new after a good clean, anyone's welcome to have it if they come down Reading way!

Be interesting to see what BMW come back with, I'm gonna suspect though, very little. Like you say it could be so many things and it doesn't really offer any clues diagnosis wise as to where to start either so would be a case of throwing parts at it until it's fixed, which quickly turns into major money on an M! Still, let us know how they get on!
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Lazy, Jerky, Horrible Throttle

Post by nichollsz4 » Mon Sep 04, 2017 2:07 pm

mad4slalom wrote: Sun Sep 03, 2017 6:10 pm Hi, does yours do this on every gearshift or just on occasion? Sport button on or off,? These can suffer from awful kangarooing on occasion if youcome off the throttle say into a mini roundabout or junction in second gear and then come back on the throttle, it can be quite dramatic, and am coninced it is the fly by wire throttle as never had it in my z3m with a mechanical throttle cable. Seems to be when you have sport button on too. Other thing i have noticed , you mention lazy throttle response, I have always found throttle slow to pick up when blipped to rev match. I will try the throttle reset too as havent done that for a couple of years. :driving:
Difficult to answer this. I'd like to say it does it on every gear change, but I can't say for absolute sure. For example, If i'm "driving like I stole it", you don't really notice. Its when your pottering around it seems to do it. I'm even going to commit and say it predominantly between 2-3k. It almost feels like a misfire.

I agree, a proper cable setup adds further feedback to the driver. My E36 m3 was brilliant in that respect. But the E46 m3 has a fly be wire setup and the two I had didn't have any issues like this whatsoever. That said, the Z4m apparently uses a different ECU to the M3, so are they comparable?

There is a blatant delay from the moment I touch the peddle. If I recorded myself driving you would be able to hear my foot hit the peddle and time the delay. Whether I put 25, 50, 75 or 100% input from 0 I get this terrible response. The only way I can overcome this is by leaving 50-10% throttle on, essentially riding the clutch

Again, there are no error codes displayed. Reset any adaptations from the EME or whatever its called, but according to the car, all is well.

My thoughts on possible culprits...

- Coil Pack/s
- Throttle Position Sensor (one of)
- Mass Air Flow
- Poor Remap
- Tired Throttle actuator

Knowing my luck, its gong to be the latter of the list as its most costly to put right but does anyone have any other thoughts?

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