UPDATED::: Z4M S54 Engine Hesitation - POLL

ph001 · Post by **ph001** » Tue Oct 30, 2018 2:37 pm

620turbo wrote: ↑Thu Jun 14, 2018 10:59 pm There is something very different between the Z4M and E46 M3 S54 implementations in this respect because E46 M3 does not do this.

Oh yes they do!

TomK · Post by **TomK** » Wed Oct 31, 2018 7:43 pm

ph001 wrote: ↑Tue Oct 30, 2018 2:37 pm Oh yes they do!

Do you have first hand experience of this then?
In the 4 years I had my m3 I never came across this symptom on any of the various boards, some which I still frequent and I still don't hear of it?
My z4m had this problem when I bought it, thankfully I fixed it shortly after although I'm still not quite sure how. 4 years on still good.
It's a horrible problem though, really detracts from the experience.

I'm also of the opinion that it's the dme used in these cars which causes the problem and is very different to the e46 dme.

samZ4M · Post by **samZ4M** » Wed Oct 31, 2018 8:34 pm

Now it’s cold again, my M is hesitating at 2500-3000 rpm, only in lower gears, suppose due to the power in them?

No other signs of a problem. Thoughts?

ph001 · Post by **ph001** » Wed Oct 31, 2018 8:44 pm

It certainly doesn’t ruin the experience as it’s only during the cold start loop which lasts 3 mins at most. Here you go.... https://forums.m3cutters.co.uk/threads/ ... -cold.809/

TomK · Post by **TomK** » Wed Oct 31, 2018 11:57 pm

Ah, that explains it. Completely different problem to what this thread is about.
The hesitation our cars can suffer from is not related to being cold or hot, it happens all the time.

buzyg · Post by **buzyg** » Thu Nov 01, 2018 1:06 am

Never had a moment's hesitation in almost 8 years.

ph001 · Post by **ph001** » Thu Nov 01, 2018 3:23 pm

TomK wrote: ↑Wed Oct 31, 2018 11:57 pm Ah, that explains it. Completely different problem to what this thread is about.
The hesitation our cars can suffer from is not related to being cold or hot, it happens all the time.

...ah, apologies. Yes can confirm that when the E46 M3 warms up there is no hesitation. Like you say though, all the engine hardware apart from the ECU and exhaust is the same so makes you think software related. Has anybody had a remap from the likes of Evolve? If that sorts it then it confirms software really.

Buzzard88 · Post by **Buzzard88** » Wed Mar 27, 2019 6:44 am

Ok so Hi everyone.. Car=Z4MC. I came upon this thread whilst looking for a fix to my problems which appear to be exactly as headlined. I only just purchased the car and it has 77,000km. During the test drive the car performed flawlessly but after a couple of weeks this hesitation started happening and has progressively gotten worse.

Once my car has had it's hesitation from idle then it purrs and screams like it should! So when stopped I usually give the car revs earlier than normal prior to releasing the clutch just so it has it's little hissy fit before the clutch is released. Once its had it's fit then all good.

The day I purchased the car I scanned it for faults and 002C9D (Lambda heater fault) showed up. The car has low k's and is in pretty clean shape under the bonnet. At least the car is reliably hesitating after warm up,,, well up until today anyway. I was so happy that the car wasn't doing it today and it was a pleasure to drive again. The only thing I did was to remove the engine cover and disconnect the 2 lambda sensors from the harness, and remove all coil packs to inspect them. Sure enough one of the Lambda sensors measured open circuit across the heater element. The coil packs looked ok and down the holes looked nice and dry. I re-installed the coil packs and re connected the lambdas. I went out for a drive and I noticed that the car was behaving and responding nicely to throttle activation, making heal & toe simple again. I can't for the life of me understand why this problem has gone at least for now but I suspect the problem will raise it's head again soon.

I have ordered new lambdas, TPS x 2, Spark plugs, Coil packs x 6, just because I want these new now. Last week I changed the MAF sensor. Later this week or weekend I will be replacing the other parts and will also give the ICV a good clean. If the car starts playing up again then I shall replace each part progressively to try and learn something. Until this morning I was pretty convinced it was the ICV.

Will try and keep the forum updated with my progress, or lack thereof.

Bill10 · Post by **Bill10** » Thu Mar 28, 2019 8:56 pm

Got the problem but not on my Z4MC. E46 330CI MSport has behaved this way for some time. M52B30 engine same as in the non M pre-facelift 3 litre Z4. Misfire when picking up from idle or on the overun. The blogs all reckon it is a leak in the crankcase breather system. I have done:-
New DISA valve;
New CCV valve;
New crankcase breather pipes.

Still no cure. Thinking plugs next or maybe airflow sensor.

Buzzard88 · Post by **Buzzard88** » Fri Mar 29, 2019 8:34 am

An update..

Have just replaced the spark plugs, coil packs, throttle body TPS with all new genuine parts. Car is still doing it. Next on list hopefully sometime this weekend is cleaning ICV, replace lower TPS. And on Monday when my new o2 sensors come then those.

I really feel it's the ICV as it can sometimes be good on one blip of throttle but most the time it is bad, which makes me think the ICV is a little sticky. Would have done it first if were not quite such a pain the backend.

Report back soon...

Buzzard88 · Post by **Buzzard88** » Sun Mar 31, 2019 11:48 am

Another update..

Thoroughly cleaned ICV, hoses, throttle bodies, butterflies. Replaced the throttle actuator sensor, inspected all lines. Problem persists. Bugger!

The ICV didn't really feel a concern when I initially removed it but once or twice I thought it was a little hesitant to move when shaking from side to side but that could have been where it was balance at the time and direction of the shake.

The procedure is not as bad as I thought. It probably took about 30 minutes to remove / disassemble, 60 minutes to clean, 60 minutes to reassemble, 10 minutes to feel disappointed about wasting my time.

Tomorrow my Lambda sensors arrive and will do the pre and post cats. If this fails to cure the problem then I don't know, maybe I will focus on the VANOS. FU&^^&%^%$%45.

pcube · Post by **pcube** » Sun Mar 31, 2019 4:06 pm

Have you tried twisting the pins on the MAF sensor connector? This seemed to do the trick for me

Matt.13 · Post by **Matt.13** » Sun Mar 31, 2019 6:55 pm

pcube wrote: ↑Sun Mar 31, 2019 4:06 pm Have you tried twisting the pins on the MAF sensor connector? This seemed to do the trick for me

Can I ask what pins you mean ?
Thanks

Buzzard88 · Post by **Buzzard88** » Mon Apr 01, 2019 12:07 pm

pcube wrote: ↑Sun Mar 31, 2019 4:06 pm Have you tried twisting the pins on the MAF sensor connector? This seemed to do the trick for me

Thanks for something.. I'm guessing you suggest to do this in case of dirty contacts and twisting them may clean them somewhat? My MAF was replaced two weeks ago as I thought that might be causing the problem as it did on my old E39 M5.

Buzzard88 · Post by **Buzzard88** » Mon Apr 01, 2019 12:21 pm

Ok so today I replaced the 2 pre cat Lambdas and the problem persists. Now it feels like

The Lambda sensor that had a faulty heater as I mentioned in my initial post had quite a bit of carbon deposit on it when the good one was fairly clean which suggests to me that the faulty heater had caused damaged eventually to the sensor so it reports incorrect values to the DME and therefore the DME is running that bank rich when it thinks it is not. Thought I was on to something there until

.

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