Z4M 2007 Problems at high speed
Discussion
Guys I am looking for some help, I own a BMW Z4M on a 07 plate.
When accelerating heavily through the gates of speed in fifth gear I can reach approx 158mph indicated, but when I try this from 120 in 6th I get the car to jump into limp mode and a limitation on revs of 1200rpm approx. I can then turn it off and back on at stand still and fault will clear, BMW does not know what the issue is and cannot help as it is out of warranty and are generally not interested.
Please could someone give me some clues as what could be the issue or if any one has had this problem, as far as i know the limiter is still fitted to the car.
The car had 2 years ago a small accident by the looks of it, with a small spray job.
The car is black, 19" allows additional engine bay torsional bars, lowered 35mm for additional stability etc.
Nick
When accelerating heavily through the gates of speed in fifth gear I can reach approx 158mph indicated, but when I try this from 120 in 6th I get the car to jump into limp mode and a limitation on revs of 1200rpm approx. I can then turn it off and back on at stand still and fault will clear, BMW does not know what the issue is and cannot help as it is out of warranty and are generally not interested.
Please could someone give me some clues as what could be the issue or if any one has had this problem, as far as i know the limiter is still fitted to the car.
The car had 2 years ago a small accident by the looks of it, with a small spray job.
The car is black, 19" allows additional engine bay torsional bars, lowered 35mm for additional stability etc.
Nick
Hello john thanx for reply,
what roads are a question lol, the problems happen in 6th from 120 + upwards only on average 124 - 130 ish.
The car then goes completely into limp mode and will not reset until ignition is switched off and back on then all is fine the fault codes are air fuel mixture every time, but friend and mechanics seem to think this is where it is on ramp down and killing the ignition circuit and running lean on the ramp down.
what roads are a question lol, the problems happen in 6th from 120 + upwards only on average 124 - 130 ish.
The car then goes completely into limp mode and will not reset until ignition is switched off and back on then all is fine the fault codes are air fuel mixture every time, but friend and mechanics seem to think this is where it is on ramp down and killing the ignition circuit and running lean on the ramp down.
Your best bet is to ask on the z4-forum, I think I've heard similar stories there so you might find an answer. Can't say I've had this issue but then I've never taken it to the limiter in 5th or 6th! Even on track I don't think I've gone much beyond 140 so is it really that big an issue?!
tjlazer said:
Your best bet is to ask on the z4-forum, I think I've heard similar stories there so you might find an answer. Can't say I've had this issue but then I've never taken it to the limiter in 5th or 6th! Even on track I don't think I've gone much beyond 140 so is it really that big an issue?!
Yes... That's really the same as saying why buy a Lambo/Ferrari/M6/911 Turbo and a pletora of other fast cars as you can only go as fast as the 70mph motorway limit on the road. Maybe the OP wants to take it to the Ring - there are two places where you would hit 165 indicated on the speedo 
Cheburator mk2 said:
tjlazer said:
Your best bet is to ask on the z4-forum, I think I've heard similar stories there so you might find an answer. Can't say I've had this issue but then I've never taken it to the limiter in 5th or 6th! Even on track I don't think I've gone much beyond 140 so is it really that big an issue?!
Yes... That's really the same as saying why buy a Lambo/Ferrari/M6/911 Turbo and a pletora of other fast cars as you can only go as fast as the 70mph motorway limit on the road. Maybe the OP wants to take it to the Ring - there are two places where you would hit 165 indicated on the speedo Thanks for the idea of back fire - missing etc, but the three times BMW have looked at it, it only shows fuel mixuture errors so would not suspect a coil pack etc or equivilent.
I undstand the factor of 70mph but owning this kind car and my general need for speed in the quiet hours (out of the country) means i do like to push a car to know what it is capable of.
I have had a couple of people mention ABS issues with alignment sensors, but seems more likely to be a 6th gear releated issue as rev range works through-out all other gear sets.
Hopefully we will all come to a more definetive answer with time and progress.
Nick
I undstand the factor of 70mph but owning this kind car and my general need for speed in the quiet hours (out of the country) means i do like to push a car to know what it is capable of.
I have had a couple of people mention ABS issues with alignment sensors, but seems more likely to be a 6th gear releated issue as rev range works through-out all other gear sets.
Hopefully we will all come to a more definetive answer with time and progress.
Nick
Might be the limiter mis working, but doubt it would be engaged at 120mph, I have just stripped out my DME and cleaned, resealed the unit as BMW found some moisture entry, on inspection PROPERLY no moisture only case corrosion so have removed PCB cleaned and resealed 90% excluding connection end.
Question looks like the DME is ment to have a seal around the outer casing in terms of a rubber seal which was not there and moisture had just started to creap into the case, I have clean PCB, and case and brackets and waterproof sealed it which will be sufficient for the forseable future, but is it ment to include a seal from the factory??
The limiter has not been removed by the way and the DME has not been chipped, as I have now inspected it!
Question looks like the DME is ment to have a seal around the outer casing in terms of a rubber seal which was not there and moisture had just started to creap into the case, I have clean PCB, and case and brackets and waterproof sealed it which will be sufficient for the forseable future, but is it ment to include a seal from the factory??
The limiter has not been removed by the way and the DME has not been chipped, as I have now inspected it!
On a 3 year old car I'm struggling to think what it can be.
The gearbox will most likely have a gear sensor (as the E36 M3 Evo's and E46 M3's do) so I'm guessing a 2007 MZ4 would as well - so that could be an issue. Though I thought it's only to tell if it's in/out of gear - so it uses a much less agressive engine map out of gear.
On a car this modern the VANOS is continuosly variable - so i doubt that's an issue only in 6th.
The throttle bodies would be electronically actuated but i doubt that's an issue either.
Don't forget that in 6th gear the load on the engine is increased (compared to other gears) - it could be a sensor mis-detecting load. Usually this is a combination of air intake temp sensor, MAF sensor and the crank sensor. I doubt it's the MAF so I think it might be worth having the air intake sensor and crank sensors tested.
And the DME would not have been chipped. It's only the older cars (pre-1996) that would be chipped as anything newer can be re-programmed throguh the OBD-II port.
The gearbox will most likely have a gear sensor (as the E36 M3 Evo's and E46 M3's do) so I'm guessing a 2007 MZ4 would as well - so that could be an issue. Though I thought it's only to tell if it's in/out of gear - so it uses a much less agressive engine map out of gear.
On a car this modern the VANOS is continuosly variable - so i doubt that's an issue only in 6th.
The throttle bodies would be electronically actuated but i doubt that's an issue either.
Don't forget that in 6th gear the load on the engine is increased (compared to other gears) - it could be a sensor mis-detecting load. Usually this is a combination of air intake temp sensor, MAF sensor and the crank sensor. I doubt it's the MAF so I think it might be worth having the air intake sensor and crank sensors tested.
And the DME would not have been chipped. It's only the older cars (pre-1996) that would be chipped as anything newer can be re-programmed throguh the OBD-II port.
Hey Guys Time for a timely update!!!!
The on going issues with speed, the car has now down shifted the problem to 5 gear also around the same ish speed.
This means ruling out the speed limiter if it was ever active on my model. I have had no problems with the DME or fault codes even relating to this.
Fault codes listed are now below
PO172
PO175
PO16A7
The codes are all air path and happen at high speed.
The last code is MAF but think this has been generated when people have been diagnosing (trying too) un-pluging etc.
Recent data diagnosis show fuel economy has dropped between 11 and 14 mpg.
I have cleaned MAF just incase and throttle response increased and the magical 6th gear issue vanished for 1 thrashing!40+.
I ordered a new ORIGINAL BOSCH MAF and fitted today the problem has been increased now issues at 80-90mph 5th and 6th gear. Same codes but generally bad running hesitating and jerky under full throttle accel throughout.
I will install old MAF tomorrow but do not believe this is the main issue.
QUESTION:
When changing MAF on Z4M E86 chassis does the ECU have adaptive software for ageing of MAF's I know 3,5,7 series do but have never heard of this for Z4M's.
Due to my un-helpfull BMW deep pocket dealer I will not be returning to them, even though the car has a 0 excess extended warranty no worth the paper its written on, for my sins I have now been to see and spoken to in-depth a company called Motor Aid in basildon, they looked at the car FREE of charge for 1 hr and could not find anything so have asked me to leave the car with them for diagnosis again which is chargeable to me, but as they change parts throughout the back and forth process will only charge me for faulty parts not any part they feels just might need to be replaced like BMW southend.
This company will hopefully help me to the point where I can resolve all issues asap, I will keep you all updated as this is a strange problem and would imagine most people are curious.
Regards
Nick
The on going issues with speed, the car has now down shifted the problem to 5 gear also around the same ish speed.
This means ruling out the speed limiter if it was ever active on my model. I have had no problems with the DME or fault codes even relating to this.
Fault codes listed are now below
PO172
PO175
PO16A7
The codes are all air path and happen at high speed.
The last code is MAF but think this has been generated when people have been diagnosing (trying too) un-pluging etc.
Recent data diagnosis show fuel economy has dropped between 11 and 14 mpg.
I have cleaned MAF just incase and throttle response increased and the magical 6th gear issue vanished for 1 thrashing!40+.
I ordered a new ORIGINAL BOSCH MAF and fitted today the problem has been increased now issues at 80-90mph 5th and 6th gear. Same codes but generally bad running hesitating and jerky under full throttle accel throughout.
I will install old MAF tomorrow but do not believe this is the main issue.
QUESTION:
When changing MAF on Z4M E86 chassis does the ECU have adaptive software for ageing of MAF's I know 3,5,7 series do but have never heard of this for Z4M's.
Due to my un-helpfull BMW deep pocket dealer I will not be returning to them, even though the car has a 0 excess extended warranty no worth the paper its written on, for my sins I have now been to see and spoken to in-depth a company called Motor Aid in basildon, they looked at the car FREE of charge for 1 hr and could not find anything so have asked me to leave the car with them for diagnosis again which is chargeable to me, but as they change parts throughout the back and forth process will only charge me for faulty parts not any part they feels just might need to be replaced like BMW southend.
This company will hopefully help me to the point where I can resolve all issues asap, I will keep you all updated as this is a strange problem and would imagine most people are curious.
Regards
Nick
As input but not directly to this issue, my E46 M3 once threw a Misfire code. It happened in Germany after a short autobahn run maybe we hit 100mph a few times but was too busy for sustained cruise at speed. Headed off into a village for lunch, coming down the hill, the engine sounded rough, then a few km later engine light on and the thing had obviously 'lost' a cylinder.
Feeling a bit peeved (family touring holiday having just started) parked up, had lunch. Phoned BMW emergency services (have good experience with these guys twice now while in EU zone). They said restart it and see what happens. I did, it was fine. Next day took to dealer close to Nurburgring (had to pay a visit since we were passing, great facility there now). They found a mis-fire fault, fiddles a bit, test drove it hard, rechecked codes - EXCELLENT service!!
Conclusion: no idea what caused it. I managed to discuss coil packs issue and they told me they fail or donlt fail, its not an intermittent fault. Not sure I am convinced.
This car has done 57k now, that misfire (a single event that shut the cyclinder down) happened at abot 50k. Later that day she sat at 140mph in 6th for 30 mins. So since I owned it at 19k the car has had zero other engine faults, and none since.
When I got home I reported the rough running that continued during the holiday and 'got worse' but no misfire. Turned out it needed a new dual-mass flywheel - replaced on warranty, that that explained some of the lead-up to the issue. Was rough as a badgers by then especially under hard acceleration.
Well I have bored myself now - its a bit off-topic, sorry. But is is related to engine fault!
Feeling a bit peeved (family touring holiday having just started) parked up, had lunch. Phoned BMW emergency services (have good experience with these guys twice now while in EU zone). They said restart it and see what happens. I did, it was fine. Next day took to dealer close to Nurburgring (had to pay a visit since we were passing, great facility there now). They found a mis-fire fault, fiddles a bit, test drove it hard, rechecked codes - EXCELLENT service!!
Conclusion: no idea what caused it. I managed to discuss coil packs issue and they told me they fail or donlt fail, its not an intermittent fault. Not sure I am convinced.
This car has done 57k now, that misfire (a single event that shut the cyclinder down) happened at abot 50k. Later that day she sat at 140mph in 6th for 30 mins. So since I owned it at 19k the car has had zero other engine faults, and none since.
When I got home I reported the rough running that continued during the holiday and 'got worse' but no misfire. Turned out it needed a new dual-mass flywheel - replaced on warranty, that that explained some of the lead-up to the issue. Was rough as a badgers by then especially under hard acceleration.
Well I have bored myself now - its a bit off-topic, sorry. But is is related to engine fault!
Edited by Davidonly on Sunday 9th January 08:52
Well afternoon all time for the constructive update.
The car has now been out of action getting of three weeks some good news some bad news anyway here we go:
Faults remaining after checking, fuel pump, solenoids, injectors, fuel pressures static and dynamic, spark plugs, mass air flow sensor, vanos units, air filter, wiring loom.
BMW told me they updated the firmware to latest edit for that DME, guess what it had not been updated this the cars/DME production and I watched them extract the log files etc, good old BMW Stealers they really do know how to lye.
Anyway after MAD updated the firmware it resolved alot of the issues etc but still jumping into limp mode in hard accelleration, so we decided the following,
Suspected DME failure as fault was internal DME air mass fault, so we decided between myself and the company that they would order a new DME £640 +VAT and if it sold the problem they would charge labour and if not they would let me have it net cost to them.
Gues what the DME and new firmware resulted in a much faster response to throttle and general running but not overal resolve.
Next step the company was doing a training seninar with BMW, so you guessed it through the back door and straight to the top of the tree for diag, unfortunatley they listed everything to check that has already been checked, so no help there, they also took the log file from the DME and tried to run scenarios etc.
In the mean time MAD also hired a rolling road and ( 4 wheel ) and let the car have it, good news to a point the rolling road allowed them to check torque, MPH, emmissions, BHP, etc.
The charts strangely was perfect for all except rpm and BHP 2700rpm and a definent shelf/flat spot appears, this information was also given to BMW etc.
As you can tell by now it has started to become one hell of a strange and irratic issue which BMW as predicted and previous experience pointed too had NO IDEA WHAT SO EVER.
So on with the story at this point MAD also said they was expecting to see a fueling issue and emmssions but everything is bang on 328bhp @ 5300rpm. I left the car there for a couple of days and decided to take it back I spoke to a gentlemen there who as I was saying I was going to take it had been speaking to a speciallist tuning company they use for BMW M Spec etc S54 engines and have come up with a suggestion that the throttle motor may be causing all the issues, so they have agreed to buy the part and if it fixes it charge me and if it dont then I do not pay anything appart from the ECU which was fair game.
Its been delivered and there fitting now so the car at present is the only one known to man with this issue and BMW cannot diagnose, at least I am working with a company that actually wants to help!!!!!
More updated soon.
The car has now been out of action getting of three weeks some good news some bad news anyway here we go:
Faults remaining after checking, fuel pump, solenoids, injectors, fuel pressures static and dynamic, spark plugs, mass air flow sensor, vanos units, air filter, wiring loom.
BMW told me they updated the firmware to latest edit for that DME, guess what it had not been updated this the cars/DME production and I watched them extract the log files etc, good old BMW Stealers they really do know how to lye.
Anyway after MAD updated the firmware it resolved alot of the issues etc but still jumping into limp mode in hard accelleration, so we decided the following,
Suspected DME failure as fault was internal DME air mass fault, so we decided between myself and the company that they would order a new DME £640 +VAT and if it sold the problem they would charge labour and if not they would let me have it net cost to them.
Gues what the DME and new firmware resulted in a much faster response to throttle and general running but not overal resolve.
Next step the company was doing a training seninar with BMW, so you guessed it through the back door and straight to the top of the tree for diag, unfortunatley they listed everything to check that has already been checked, so no help there, they also took the log file from the DME and tried to run scenarios etc.
In the mean time MAD also hired a rolling road and ( 4 wheel ) and let the car have it, good news to a point the rolling road allowed them to check torque, MPH, emmissions, BHP, etc.
The charts strangely was perfect for all except rpm and BHP 2700rpm and a definent shelf/flat spot appears, this information was also given to BMW etc.
As you can tell by now it has started to become one hell of a strange and irratic issue which BMW as predicted and previous experience pointed too had NO IDEA WHAT SO EVER.
So on with the story at this point MAD also said they was expecting to see a fueling issue and emmssions but everything is bang on 328bhp @ 5300rpm. I left the car there for a couple of days and decided to take it back I spoke to a gentlemen there who as I was saying I was going to take it had been speaking to a speciallist tuning company they use for BMW M Spec etc S54 engines and have come up with a suggestion that the throttle motor may be causing all the issues, so they have agreed to buy the part and if it fixes it charge me and if it dont then I do not pay anything appart from the ECU which was fair game.
Its been delivered and there fitting now so the car at present is the only one known to man with this issue and BMW cannot diagnose, at least I am working with a company that actually wants to help!!!!!
More updated soon.
Another update,
the motor unfortunately did not resolve the issue, so they have not charged me but are now unfortunately out of questions and too many answers,
in response the the injector question all fuel injection systems are working correctly and also emmissions so this is not a viable option unfortunately, I was it was that easy.
It has been booked back in with BMW synter now by MAD so we shall see if we get any further
the motor unfortunately did not resolve the issue, so they have not charged me but are now unfortunately out of questions and too many answers,
in response the the injector question all fuel injection systems are working correctly and also emmissions so this is not a viable option unfortunately, I was it was that easy.
It has been booked back in with BMW synter now by MAD so we shall see if we get any further
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