UPDATED::: Z4M S54 Engine Hesitation - POLL

[darkpker88]

Ah, ok possibly the message has been passed on wrong across parties, apologies! :roll:

Unfortunately I from the midlands so no where near you, thanks for the offer tho

I will replace both sensors with new ones then put the original actuator back on, Ill then get the garage to recalibrate, etc and check over my installation (wondered a possible air leak may be the cause but surely wouldn't effect it like this).

Cheers for your input guys!

 

[mmm-five]

Could you have inadvertently knocked the MAF when you did the Eventuri?

 

[darkpker88]

Possibly, I cleaned the MAF connectors while I was there with stabilant 22, just wouldn't have thought the MAF would have caused only faults when on full throttle.

It will go all the way up to 7/8k on 50-60% throttle without hesitation, just that last push and it doesn't like

 

[Rene_Z4MC]

I would suspect ignition, sparkplugs, knock sensor telling the ECU to cut.
IDK, just thinking out loud.

 

[darkpker88]

Oh jesus, didn't realise it could cause a knock on problem, fingers crossed it doesn't lead to more and more repairs.

The garage did say they got a fault code of it saying pointing to the actuator but I have heard faulty sensors can sometimes be at fault even with the fault code being for the actuator?

 

[mmm-five]

Possibly, I cleaned the MAF connectors while I was there with stabilant 22, just wouldn't have thought the MAF would have caused only faults when on full throttle.

It will go all the way up to 7/8k on 50-60% throttle without hesitation, just that last push and it doesn't like

That's almost exactly what mine was doing, but it wouldn't just hesitate it would cut out completely - which is a bit disconcerting when you're in the middle of a B-road overtake

Light to medium throttle was fine - only ever happened on 75-100% throttle in 3rd/4th gear.

Originally thought it was the Gruppe-M, but swapping to the original airbox didn't resolve it, and the error codes were generic 'too rich on bank x' ones.

Took it to Darren Wood for an Inspection and asked them to have a look at it. They said it was the MAF and a replacement had resolved the issue.

Not had a recurrence in about 5,000 miles (including 40 laps of the 'Ring).

Should have got them to do my radiator at the same time, but I was using the Inspection as a feeler before I started using them as a local alternative (for the little stuff) to my Essex (soon to be Dorset) based indy/mate.

 

[Rene_Z4MC]

Oh jesus, didn't realise it could cause a knock on problem

Don't worry, I'm no expert, just recalled similar behaviour happening to my Delta Integrale. All fine except under full throttle it would suddenly violently shake, stutter and bang. New sparkplugs and everything was fine again.

 

[darkpker88]

Ah OK, I may just get a new MAF sensor aswell just to be sure, do they need calibrating if im swapping them aswell do you know?

As for sparks I think they were changed not long ago so fingers crossed I don't need another new set.

 

[darkpker88]

Right, another garage has come back and said the throttle valve unit is faulty and getting stuck at 90%....
Is this different to the throttle actuator?
Quote is around 600 including programming / calibrating, asked quite a few questions about could it just need reprogramming due to me manually opening the bodies to clean it, however for a BMW specialist they didn't really have much knowledge of the s54 engine :|

 

[mmm-five]

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

 

[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 .

 

[Anonymous]

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