Z4M EML, Rough Idle and Hesitant Drive

D

daveyc86

Member
 Surrey
Hi All,

As per above really.

I bought my first Z4M coupe a couple of weeks ago and last week on the M25 was reduced to 4 cyclinders if not less! and the EML, DSC and Amber Engine Emissions light.

I pulled over and switched her off to then be greeted with an eratic idle. I turned her off again and left it for a couple of minutes. Upon restart the car was fine all bar the Engine Emissions light.

I took the car back to BMW specialist I bought the car from and the code stored related to the Cam Sensors. The code was cleared, car driven and the code did not re-appear as a current fault. Fast forward two days and the probably happend this morning as I started the car to leave for work. It will be going in tonight to have the sensors replace tomorrow.

I wanted to check if anyone else had experienced this? It's an 06 plate with 50k on the clock, which has only every had 2 things replaced under warranty. A hinge on the glove box and rear shocks. Other than that it seems like it's been screwed together properly.

Interestingly both times the problem has occured the morning after I've brimmed the tank. However I think this is unrelated as the first time I was about 40mins into my journey whereas this time was on inital startup.
 
Firstly welcome to the Z4 forum.

Secondly, sorry to hear about your early ownership woes. My own car suffered an oxygen sensor failure shortly I had it, so EML came on, but nothing else and a few others have described the symptoms you mention, meaning you're not alone. Certainly I've had cam sensors go on previous BMWs I've owned so am not surprised.

Can't really understand why the fault was simply cleared without further investigation but presumably the "BMW Specialist" you bought it from are covering the cost of repair such a short time after you bought it under the sale of goods act and all that?
 
I had the O2 sensor too.

Failure of the camshaft sensor isn't unusual, but there haven't been too many on here. Hopefully the new one has sorted it.
 
The only thing that i've experienced similar to what you're describing is when i had faulty O2 sensors and continued to drive the car normally nevertheless. At first it was just fine but then it started an erratic idle and would run very rich and the engine would be very rough up to 3-4k RPM. I replaced them at that point and all was well again. I only had the amber Check Engine Light on though, not the EML.

Hope you get to the bottom of it.
 
Hi guys,

Thanks for the replies, apologies for my lack of response, things have been busy at work (I'm still working now) however it appears with a more thorough diagnostic code reader, it appears to be a faulty MAF sensor.

This was my original thought when it first happened. Anyway, I have the car back and it's a completely different animal. It just flies, feels like there's an extra 50 horses under the bonnet!

Gear changes feel smoother and the car seems more compliant through the rev range.

All repaired under warranty...very happy.
 
I spoke to soon, started the car in this evening to be greeted by the EML and rough idle...it took a few restarts to clear this time. The car has been good all week so it seems strange. After the EML and rough idle cleared I have the exhaust emissions light...looks like it could have been the lambda or cam sensors after all.

Suffice to say it will be going back to the dealer again tomorrow...this is really taking the shine off buy the car.
 
:(

From what most guys experience on this forum the lambda sensors usually go by 50k. I'm at 47 and i've had them go twice so far... Most probably it's the rubbish fuel quality here in Cyprus.
 
As expected I guess, but I bet it's due to a change in fuel, get this a few times with new owners on reasonable mileages
 
You must log in or register to reply here.
Back
Top Bottom