Z4M Engine Fault Dangerous Help

[nix1983]

Afternoon guys,

Looking for some help really some of you may have been following other forums with this issue listed but though id try directly on here and having limited or no success.

Were to start car specs:

2007 Z4M

Imola Red interior

Black Exterior

19" alloys

15,000 miles

The issues:

Car accelerates fine under soft touch of the throttle, however when planting your foot it hesitates fluffs and dumps engine into limp mode ish like 1200 rpm hunting, turn off and restart and clears all faults and is fine again!!

I have had it on a rolling road and all emissions are fine, fuel mixtures, injectors oxygen probes, MAF fuel filter, fuel pressure etc etc etc.

It has been in MAD and BMW now for three weeks and three weeks and no one can find anything wrong with the car besides they know that the fault is there and dangerous.

The car apparently has had a small accident at some time in its life which is not unusual for most cars nowadays, but they have spent 23hrs and cannot find the issue and as they suspect the car may have had a repair at some point they will not uphold the warranty even though the car has been fine previously so it has just developed this issue.

And now want me to pay for there time before they will go any further even though they do not know if it is warranty or not!!!

Some one please help I am not made of money and love to car but need help.

Thanks

Nick

[Guest Mister Dabsy]

Classic example of fuel and air mixtures pal...

Because BMW's use MANY computers to control poo like that, could be your MAF sensor, Lamda or even throttle body sensors mukka :unsure:

The reason a garage/dealer cannot find the faults is that they rely on the afore mentioned computers Grrrrr.... Sad really but just clean the INTAKE system FULLY and i promise that you will see an improvement...

DAZ

BTW have a look at your spark plugs too.... They all need to have a bieige tint on them pal...

[nix1983]

Thanks for the tips,

unfortunately all fuel and air mixtures have been checked on the rolling road etc, so i would think unlikely but worth a thought.

A piece of information I left out is that both garages have the fault INTERNAL DME MAFS FAULT, now the DME has been replaced with a brand new unit and wiring loom checked and MAF changed x4 lol.

The only thing I know has not been checked with be the spark plugs but I would expect miss fire issues or rich / lean mixtures all running mixtures are perfect, which is the reason why they are stuck and just blaming the accident or what ever now. They have two chances of getting any cash out of me for something they still do not know is a warranty or not.

I seriously need some help, I am going down the route monday or possibly getting the car back and taking the engine out myself and stripping all wiring looms etc out of the car but I cannot see this being the issue.

The told me that the chassis earth being loose could back feed the DME what a load of bull, the DME would show a fault and cause other issues besides running Perfect except under full throttle conditions.

I am just getting into a hole with BMW they have never ever had a recorded fault of this kind and only interested in getting as much cash as possible for a unknown fault its not my fault that they have spent 23 hrs on a vehicle listening to the computer that has never seen this fault why should I pay for there limited fault finding skills because they are told to use there computers to fault find a fault they have never heard of just sounds like they are trying to make money and work!!

Nick

[Guest Mister Dabsy]

Could be the coil cartridges then as these often don't return codes... TBH I think it is electrical :huh:

[nix1983]

Nutter,

Problem is when the car is cold it runs fine full rev range no hesitation or dying,at a stand still or running on the move so I would assume coil packs once they start to dye normally cause issues all the time etc.

The fault is internal DME fault MAF which is why they are confused and to be honest it is strange.

A couple of people have mentioned Vanos units but again they would cause issues all the time not only when hot, as far as I know anyway.

Why they dont just bite the bullet and purchase a full set of sensors and replace one at a time till they are all replaced and the problem is gone I dont know it would have been quicker and cheaper for them.

Thanks

Nick