UPDATED::: Z4M S54 Engine Hesitation - POLL

[Herminator]

Didn't exdos mention something about the Z4MC throttle body not opening all the way -when he was comparing it to his Z3MC?

Exactly what I thought when I read "stuck at 90%"
ie. apparently normal

[Adam D]

Didn't exdos mention something about the Z4MC throttle body not opening all the way -when he was comparing it to his Z3MC?

Exactly what I thought when I read "stuck at 90%"
ie. apparently normal

Something I noted when browsing the evolve tuning website was the statement that their remap adjusts the throttle maps for 100% opening. Does anybody have one of their maps and does the engine behave better as a result?

[AndyBeech]

I think it's more like 76% full throttle, INPA or DIS confirms this, can't remember which.
Why it is this I've no idea, no-one else seems to know either. I can't see the benefit in opening to 100% though, BMW clearly programmed it that way for a reason as it wouldn't be hard to program it to open 100% at full throttle if it was beneficial. Baffles me, maybe Evolve can explain.........

[Argenta]

I have the hesitations too, mines around 100k miles or 156000km's.
Very annoying and making the car difficult to drive anywhere near smoothly.
Only tried the throttle reset but it doesnt do it.

[Rene_Z4MC]

I have the hesitations too, mines around 100k miles or 156000km's.
Very annoying and making the car difficult to drive anywhere near smoothly.
Only tried the throttle reset but it doesnt do it.

First try to thoroughly clean the IACV, relatively easy/cheap job and quite a good chance on solving the issue.

[Argenta]

Thanx, I'll give it a try!

[hoffrock]

2007 ZMC with 63k.

Ok so I was having some serious intermittent hesitation issues! It would feel like a misfire when blipped from idle and would then sink so far it almost stalled. Not to mention leaving junctions and almost stalling from the revs falling. Blipping/rev matching on a downshift became impossible.
After the initial stutter was over it would rev like freely and go like a scolded cat, But slow driving was a nightmare.

I decided I had enough of it and needed it fixed.

I tried a Throttle reset with the ignition but to no avail.

Popped to Euro Car parts, Bought two new TP-Sensors and a load of Carb cleaner.

-I took off the air-box, cleaned the mating surfaces between the Throttle Bodies and the box (it was covered in what looked like a pollen build up)
-Opened up the butterflies and cleaned all the surfaces inside the TBs. (they were coked up with black residue)
-Replaced both upper and lower Throttle position sensors.
-Took off the Idle control Valve and gave it a damn good swilling with Carb cleaner. I did the same for some of the piping. (Loads of black/yellow/brown gunk came out)
-Put it all back together cleaning the rubber mating surfaces. I wanted to insure there were no air leaks that were causing an issue.

Took it for a blast up the road, and it so far seems that the issue is gone . No more stuttering or dipping back on idle. Its back to being the sweet responsive machine it was supposed to be!
Hopefully the problem doesn't rear its ugly head again. If it does I may just replace the ICV. Shame they are almost £200 though...

Here is the engine-bay mid fix:

[2dogs]

Great write up, fingers crossed all sorted .

[sniffer]

2007 ZMC with 63k.

Ok so I was having some serious intermittent hesitation issues! It would feel like a misfire when blipped from idle and would then sink so far it almost stalled. Not to mention leaving junctions and almost stalling from the revs falling. Blipping/rev matching on a downshift became impossible.
After the initial stutter was over it would rev like freely and go like a scolded cat, But slow driving was a nightmare.

I decided I had enough of it and needed it fixed.

I tried a Throttle reset with the ignition but to no avail.

Popped to Euro Car parts, Bought two new TP-Sensors and a load of Carb cleaner.

-I took off the air-box, cleaned the mating surfaces between the Throttle Bodies and the box (it was covered in what looked like a pollen build up)
-Opened up the butterflies and cleaned all the surfaces inside the TBs. (they were coked up with black residue)
-Replaced both upper and lower Throttle position sensors.
-Took off the Idle control Valve and gave it a damn good swilling with Carb cleaner. I did the same for some of the piping. (Loads of black/yellow/brown gunk came out)
-Put it all back together cleaning the rubber mating surfaces. I wanted to insure there were no air leaks that were causing an issue.

Took it for a blast up the road, and it so far seems that the issue is gone . No more stuttering or dipping back on idle. Its back to being the sweet responsive machine it was supposed to be!
Hopefully the problem doesn't rear its ugly head again. If it does I may just replace the ICV. Shame they are almost £200 though...

Here is the engine-bay mid fix:

Nice one. I am pretty sure in most cases, this is the ICV.

Mine is now back to dog mode again so I need to give it a clean up. I may well just replace the ICV.

Once again, anyone who stumbles onto this thread and is having cold running issues, hesitation, flat spot, jerkiness during warm up, this is NOT the cure. For this, you likely need a DME update.

[Kingash]

I think it's more like 76% full throttle, INPA or DIS confirms this, can't remember which.
Why it is this I've no idea, no-one else seems to know either. I can't see the benefit in opening to 100% though, BMW clearly programmed it that way for a reason as it wouldn't be hard to program it to open 100% at full throttle if it was beneficial. Baffles me, maybe Evolve can explain.........

Does the e46 M3 open to 100%? Same engine? Maybe bmw didn't want it to outperform it by that much? I had a play with an e46 m3 the other day and o was suprised i pulled on him. This is just an idea most of the time I don't know what im going on about haha

[Bing]

I think it's more like 76% full throttle, INPA or DIS confirms this, can't remember which.
Why it is this I've no idea, no-one else seems to know either. I can't see the benefit in opening to 100% though, BMW clearly programmed it that way for a reason as it wouldn't be hard to program it to open 100% at full throttle if it was beneficial. Baffles me, maybe Evolve can explain.........

Does the e46 M3 open to 100%? Same engine? Maybe bmw didn't want it to outperform it by that much? I had a play with an e46 m3 the other day and o was suprised i pulled on him. This is just an idea most of the time I don't know what im going on about haha

It's not just you that doesn't know what they're on about... I didn't really click that our cars have 6 throttle bodies until I saw that pic

[AndyBeech]

I think it's more like 76% full throttle, INPA or DIS confirms this, can't remember which.
Why it is this I've no idea, no-one else seems to know either. I can't see the benefit in opening to 100% though, BMW clearly programmed it that way for a reason as it wouldn't be hard to program it to open 100% at full throttle if it was beneficial. Baffles me, maybe Evolve can explain.........

Does the e46 M3 open to 100%? Same engine? Maybe bmw didn't want it to outperform it by that much? I had a play with an e46 m3 the other day and o was suprised i pulled on him. This is just an idea most of the time I don't know what im going on about haha

I believe the M3 has been confirmed to open to 100% but not tested it myself. Same engine, different DME though. The Evolve map claims to change ours to 100% opening amongst other things to achieve better power but no idea how much the throttle opening to 100% correlates to the bhp increase, I would guess at not a lot tbh. Both engines make the same bhp regardless of the throttle position so there was obviously some method behind it. Worth an email to ask.
I can't see BMW would be fussed about the Z4M outdoing the M3, it was at the end of its sales life by the time the zed M was released anyway so not really direct competition.

[Stuart Truman]

Hopefully I'll have something to contribute to this soon. I started having this problem a few months ago, but when I tried to show the techs at Dick Lovett the car behaved impeccably. They did the throttle reset "just in case" but I'd already done that. Anyway, fast forward to the last few weeks and it's become quite severe and added stalling as you pull up to a stop into the mix. I took it back to Lovetts and this time the tech saw it all happening. They've got the car now and are keeping it overnight as I think I've also got the beginnings of a VANOS rattle when cold. With the stalling as you brake to a halt, I wondered if I'd got a problem with a vacuum tube and the tech tended to agree. He's going to use a smoke machine to pressurise the inlet system and other pipes to test for leaks.

[Stuart Truman]

Progress to date, dealer is recoding the car, something didn't take and the car is bricked. They have to replace a module (don't know which)

[nick_z4]

Progress to date, dealer is recoding the car, something didn't take and the car is bricked. They have to replace a module (don't know which)

It'll be interested to see what they find, mine hesitates mainly when cold but its started to do this a little at low revs when warm too