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Lazy, Jerky, Horrible Throttle

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AndyBeech
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Lazy, Jerky, Horrible Throttle

Post by AndyBeech » Mon Sep 04, 2017 2:32 pm

nichollsz4 wrote: Mon Sep 04, 2017 2:07 pm 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?
Yup M3 and Z4M have different DME's though exactly the same engine.

I would personally try TPS first, but not going to give that as solid advice as it's you're money and it could be something completely different!

If you get BMW (INPA) diagnostics on it, might be worth a try. You can find out a fair bit by just looking at the values for the various engine component's. Plus it might be storing codes in INPA but just not throwing an EML light yet, seen this a few times, maybe not but might give a clue.
I would also add pre cat o2 sensor's to you're list. Again should throw an EML if failed / failing but not necessarily, but a well known part to fail due to their location.

Might be worth biting the bullet and getting it to a decent indy, as you can see with that list, the cost's can easily escalate if you start replacing part's first without proper diagnosis.
Z4MR - Gruppe M, Bilstein PSS10, CSL's + 18" CSL reps with semi's, RTAB Limiters, Powerflex’d, PF Camber Arms, K-Sport BBK / RSL-29, GC Camber Plates, Strut Brace, Exhaust valves, custom brake cooling, complete underside refresh!

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Lazy, Jerky, Horrible Throttle

Post by Sam1977 » Mon Sep 04, 2017 7:07 pm

D4dawg wrote: 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
Calm down ....
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nichollsz4
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Lazy, Jerky, Horrible Throttle

Post by nichollsz4 » Mon Sep 04, 2017 7:12 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 ?
I'm not not sure in this to be honest. If there was an issue with the idle air control valve, would it not idle properly? Bearing in mind that other than this throttle issues, it runs and performs fine.

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Lazy, Jerky, Horrible Throttle

Post by nichollsz4 » Mon Sep 04, 2017 7:15 pm

AndyBeech wrote: Mon Sep 04, 2017 2:32 pm
nichollsz4 wrote: Mon Sep 04, 2017 2:07 pm 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?
Yup M3 and Z4M have different DME's though exactly the same engine.

I would personally try TPS first, but not going to give that as solid advice as it's you're money and it could be something completely different!

If you get BMW (INPA) diagnostics on it, might be worth a try. You can find out a fair bit by just looking at the values for the various engine component's. Plus it might be storing codes in INPA but just not throwing an EML light yet, seen this a few times, maybe not but might give a clue.
I would also add pre cat o2 sensor's to you're list. Again should throw an EML if failed / failing but not necessarily, but a well known part to fail due to their location.

Might be worth biting the bullet and getting it to a decent indy, as you can see with that list, the cost's can easily escalate if you start replacing part's first without proper diagnosis.
I've had it plugged into BMW diagnostics, but found nothing. Is the INPA diagnostics separate? I can't remember.

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Post by Scooba_Steve » Mon Sep 04, 2017 8:27 pm

INPA can give you live values
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Post by TomK » Mon Sep 04, 2017 9:19 pm

nichollsz4 wrote: Mon Sep 04, 2017 2:07 pm 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?
I have a spare throttle actuator, MAF, coil pack (x6), pre cat 02 sensor, and possibly somewhere a TPS, all known to be good.
Happy to lend them to you if that helps, drop me a pm if so.
MC[IB], CSL airbox, Schrick 288/280 cams, 4.44FD, UUC SSK, SS race cat back, AP CP9660[F]/5144[R] brakes, Apex ARC-8 with AR-1 or PS5, KW ClubSport 2-way, Turner spherical arms, PMC uniball rtab, VB engine mounts, Rogue pulleys & RSMs, Tillett B6, half cage

D4dawg

Lazy, Jerky, Horrible Throttle

Post by D4dawg » Mon Sep 04, 2017 9:51 pm

nichollsz4 wrote: Mon Sep 04, 2017 7:12 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 ?
I'm not not sure in this to be honest. If there was an issue with the idle air control valve, would it not idle properly? Bearing in mind that other than this throttle issues, it runs and performs fine.
Possibly just adding to issue perhaps as sometimes it's the illogical that becomes the logical :)
Let's see what outcome is interested upon this

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Post by AndyBeech » Mon Sep 04, 2017 10:54 pm

TomK wrote: Mon Sep 04, 2017 9:19 pm

I have a spare throttle actuator,

I would be interested in that...! Guess it's a straight swap, as in doesn't need setting up apart from bolt on bolt off...?
What caused you to change it out originally by the way Tom?
Z4MR - Gruppe M, Bilstein PSS10, CSL's + 18" CSL reps with semi's, RTAB Limiters, Powerflex’d, PF Camber Arms, K-Sport BBK / RSL-29, GC Camber Plates, Strut Brace, Exhaust valves, custom brake cooling, complete underside refresh!

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Post by TomK » Mon Sep 04, 2017 11:52 pm

AndyBeech wrote: Mon Sep 04, 2017 10:54 pm
TomK wrote: Mon Sep 04, 2017 9:19 pm

I have a spare throttle actuator,

I would be interested in that...! Guess it's a straight swap, as in doesn't need setting up apart from bolt on bolt off...?
What caused you to change it out originally by the way Tom?
Sure, no problem. It was from my old m3cs which I had to break, kept parts I might need. I not so recently tested it in my car as I was fault finding another issue, it worked fine. Correct, it's a 10 min job once you've got the airbox off.
MC[IB], CSL airbox, Schrick 288/280 cams, 4.44FD, UUC SSK, SS race cat back, AP CP9660[F]/5144[R] brakes, Apex ARC-8 with AR-1 or PS5, KW ClubSport 2-way, Turner spherical arms, PMC uniball rtab, VB engine mounts, Rogue pulleys & RSMs, Tillett B6, half cage

nichollsz4
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Lazy, Jerky, Horrible Throttle

Post by nichollsz4 » Tue Sep 05, 2017 1:21 pm

TomK wrote: Mon Sep 04, 2017 9:19 pm
nichollsz4 wrote: Mon Sep 04, 2017 2:07 pm 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?
I have a spare throttle actuator, MAF, coil pack (x6), pre cat 02 sensor, and possibly somewhere a TPS, all known to be good.
Happy to lend them to you if that helps, drop me a pm if so.
That would be brilliant! I have dropped you a PM. Thanks!

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Post by DevonPaul » Thu Sep 14, 2017 6:28 pm

Sam1977 wrote: 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
I'm reading this with interest as the wifes car does exactly the same, so much so that she sometimes avoids a route where we exit uphill onto a small but fast flowing roundabout. She's actaully losing confidence in the car and thinking of swapping to a Cayman :o

At idle, if I stab the throttle the revs dip then pick up, if I press gently all is well. When pulling away quick-ish it is very easy to give a bit too much throttle, the instinct then is to lift off slightly, which bogs the car down and leads to kangaroo-ing. My solution is that if the revs rise too much I dump the clutch and let the electronics keep me out of the local paper. It seems like the first 20% of travel gives about 50% throttle, then the rest comes in much more gently - almost the opposite of what you would expect (certainly my Maser only really kicks in with the pedal more than halfway).

I did wonder if it is partially down to the bottom hinged pedal - I find it a bit better if I consciously put my whole foot on it rather than pressing with the toe as I do in other cars as this reduces the lever effect on the pedal.

I know someone who is a software genius - does Superchips stuff and bespoke mapping. Sadly he's not well but I'm wondering about asking him to do a more sedate throttle map.

Paul
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Post by Sam1977 » Fri Sep 15, 2017 5:03 pm

DevonPaul wrote: Thu Sep 14, 2017 6:28 pm
Sam1977 wrote: 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
I'm reading this with interest as the wifes car does exactly the same, so much so that she sometimes avoids a route where we exit uphill onto a small but fast flowing roundabout. She's actaully losing confidence in the car and thinking of swapping to a Cayman :o

At idle, if I stab the throttle the revs dip then pick up, if I press gently all is well. When pulling away quick-ish it is very easy to give a bit too much throttle, the instinct then is to lift off slightly, which bogs the car down and leads to kangaroo-ing. My solution is that if the revs rise too much I dump the clutch and let the electronics keep me out of the local paper. It seems like the first 20% of travel gives about 50% throttle, then the rest comes in much more gently - almost the opposite of what you would expect (certainly my Maser only really kicks in with the pedal more than halfway).

I did wonder if it is partially down to the bottom hinged pedal - I find it a bit better if I consciously put my whole foot on it rather than pressing with the toe as I do in other cars as this reduces the lever effect on the pedal.

I know someone who is a software genius - does Superchips stuff and bespoke mapping. Sadly he's not well but I'm wondering about asking him to do a more sedate throttle map.

Paul
Hi Paul. I actually started a new thread on this because my issue seemed different to that of the original OP but it seems your problem is the same as mine. So hopefully you have read that thread. I seem to have resolved the problem with BMW inspecting the car and finding it didn't have OEM plugs. I was extremely sceptical about this being the cause but since I haven't had the car very long and have no idea when they were last changed I told them to change them. Picked up today and no longer have the rev drop when pulling away at low revs. I can recreate SORT OF the rev drop now but only at idle and only by doing stuff like stabbing and repeatedly stabbing the throttle before it even revs up causing it to hesitate slightly but in terms of normal driving and not messing around with it at idle it seems fine.

Seems to be a myriad of similar but in reality different issues with this car (that must be the DME since thats the only difference between M3 and Z4M engine as far as I know) but most - and I hope I am an exception - don't ever seem to get rid of it!

I wonder why they had a different DME in this model - anyone know?

All the best
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

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Lazy, Jerky, Horrible Throttle

Post by nichollsz4 » Thu Sep 21, 2017 9:27 am

UPDATE:

I was troubleshooting my car over the weekend and whilst doing, a coil pack completely failed on me. I had a spare coil pack from my old m3 which I knew was relatively new. Swapped out and we were back in business.

Whilst identifying the failed coil pack, I noticed a wash of different aged and branded coil packs where installed. Some were originals, others were old style Bosch coil packs. The original coil packs are made by Bremi and were known to be rubbish. I actually swapped them out on my old M3 when it developed a very faint, but annoying misfire. Its why I had a spare one in the first place.

So I ordered a full set of new Bosch coils packs and fitted on Tuesday. Since then, everything seems to be working as it should. I know longer seem to have lacy, jerky, horrible throttle and behaves in all conditions. It evens starts quicker!

Its worth noting that the car had never shown any indication of misfiring or failing at any time, so if you are having an issue similar to me, I would check the coils and if they are still on the original, replace them.

I managed to source a full set from car parts for less for just under £97 using code SAVE10 (Quidco also have 2.1% off)

https://www.carparts4less.co.uk/cp4l/c/ ... 532&000197

I will continue to monitor the car and will report back any feedback relevant to this subject. For now though, all is well. :driving:
Last edited by nichollsz4 on Thu Sep 21, 2017 12:30 pm, edited 1 time in total.

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Post by ph001 » Thu Sep 21, 2017 10:21 am

Great result. You wouldn't have coil packs high on the list to change with those symptoms so well done.
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Sam1977
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Post by Sam1977 » Thu Sep 21, 2017 7:41 pm

nichollsz4 wrote: Thu Sep 21, 2017 9:27 am UPDATE:

I was troubleshooting my car over the weekend and whilst doing, a coil pack completely failed on me. I had a spare coil pack from my old m3 which I knew was relatively new. Swapped out and we were back in business.

Whilst identifying the failed coil pack, I noticed a wash of different aged and branded coil packs where installed. Some were originals, others were old style Bosch coil packs. The original coil packs are made by Bremi and were known to be rubbish. I actually swapped them out on my old M3 when it developed a very faint, but annoying misfire. Its why I had a spare one in the first place.

So I ordered a full set of new Bosch coils packs and fitted on Tuesday. Since then, everything seems to be working as it should. I know longer seem to have lacy, jerky, horrible throttle and behaves in all conditions. It evens starts quicker!

Its worth noting that the car had never shown any indication of misfiring or failing at any time, so if you are having an issue similar to me, I would check the coils and if they are still on the original, replace them.

I managed to source a full set from car parts for less for just under £97 using code SAVE10 (Quidco also have 2.1% off)

https://www.carparts4less.co.uk/cp4l/c/ ... 532&000197

I will continue to monitor the car and will report back any feedback relevant to this subject. For now though, all is well. :driving:
Result! So yours was coils mine was plugs - neither of these things came up anywhere when I researched the problem. Good info for others hopefully!
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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