Z4-forum.com

I've been surprised by how many people are putting up with the engine hesitation from idle issue, that so many of us are experiencing. It'd be interesting to get an idea of numbers for who has the problem, who doesn't and who's in between

bertman

14/7 UPDATE

This is excellent guys 31 votes in only 24 hours and some great info in the thread

Based on your votes / comments & info from other threads I'm to piece together some facts about the problem

Facts I believe can be deduced from information submitted:
This is not a quirk of the S54 (62% of cars have never had it happen)
Mileage (Occurs on high and low mileage cars)
If the fault is in it's earlier stages, fuel can mask the problem (owners reporting being able to eliminate the fault by switching fuels)
The issue is progressive (some cars have had it happen but are able to eliminate it with different fuel, some can't)
Fuel is not the cause of the problem (owners without the fault reporting they can run their vehicle on low octane fuel without the fault)

Confirmed NON fixes:
ECU Flash
Clean MAF
Clean Idle Control Valve
Clean throttle body
Valve Lash
Oxygen / Lambda Sensor (taken from other thread)

Potential Fixes:
Coils
Clean injectors (not with a fluid but a proper remove & clean or replace)
Throttle position sensor
Throttle switch? (is this the correct name)
Accelerator pedal module
more...?


NB - I am not a BMW technical guru. I am just compiling and making assumptions based on presented info for the betterment of all owners and the forum
I've updated the 1st post so anyone new to the thread can see our conclusions to date

I don't really know what this is but pretty sure I haven't got it. A lot of people talk about it on here. My car drives great

It's the hesitation some of us get when we first hit the gas when the car is idling. If you haven't got it, then vote accordingly so we can get a percentage of affected cars

no issues here...

Not at all. No issue here.

No Issue with mine either

Not happened to mine, 06 and 38,000 miles, was running V Power but now on Momentum 99 for the last 3 fill ups

Nope me neither (62,000 Miles & 06)

I have this issue and I've did the following trying to fix it:
- cleaned throttle bodies;
- cleaned ICV;
- cleaned MAF;
- checked and adjusted valve lash;
- ran a few bottles of LiquiMoly injector & valve cleaners;
- full reset of the ECU (by discinnecting the negative lead of the battery and leaving the car like that for a week);
- installed an ECU tuning (Evolve-R) - not for that purpose, but the conclusion is that the hesitation is not ECU related.
None of the above solved it, nor at least improved it.

Next suspects on my list:
- Lamda sensors;
- throttle position sensor;
- accelerator pedal module.

EDIT: Info added on JUl. 14, 2012: mileage: ~ 60.000 Km (37.500 miles)

Can I suggest we ad your miles on as well/age this maybe an interesting stat? As they maybe an age/ miles cars are affected ? I just edit mine now

I've had the same problem, only slight hesitation previously. I've starting using shell v power and it seems to be a lot better. No hesitation anymore.
Has anyone else tried the same?
Year 2006
Mileage 41,000

No problems with mine at 18k miles,run purely on super unleaded.

No problems I've noticed
56/30k

No problems as far as i can tell. I certainly dont get the rpm dip when the revs drop back down (which was on a video one of the other threads)

Maybe we all need to take videos of throttle blipping and post them up for comparison. Perhaps some people are just more sensitive to these things.... i generally dont ask for much from the car straight from idle

Not an issue for me although i do think that 340 bhp from a 3.2 litre engine was always likely to make idle in traffic 'lumpy' enough to cause the occasional splutter. It seems as though some cars are far worse than others.

reading through comments on old Z3M/M3 forum threads hesitation/spluttering were known problms with the S54 engine and kangarooing was an issue even with M3 SMG gearboxes. Doesn't seem to be only on the Z4M that this has been an issue for some. One guy says replacing the throttle switc cured the problem on his car.