Z4 rough idle followed by check engine light

[SGRG]

Z4 rough idle followed by check engine light

First of Merry Christmas everyone!! Right the Z has been acting up a lot of late. After a little over a week of inactivity i decided to start her up yesterday. As soon as i start the engine i could see that there was something wrong right away. The car was in idle but i could feel the vibration throughout the car. I left the car running for few more seconds and the engine light came on at which point i immediately turned car off.

I took this video today:
[youtube]stxO8SGPIhA[/youtube]

The car is an 03 3.0 se with 42k on the clock. I bought her in August 10 and the independent dealer did say they did an oil service as well before i picked her up. However, he said he forgot to reset the service indicator, which was bit suspicious but i was too excited and too far home to actually start making a fuss about it. I didn't have any issues at all until November came around.

1. Coolant light came on in early Nov, so i did a quick search here and spoke to the local BMW dealer as well and the conclusion was it just needed coolant topping up. So bought some coolant from the dealer mixed it up with some de-ionised water from Tesco 50/50 mix.



So that was that, coolant light issue was fixed although i idid start seeing more white smoke/mist after the top up coming from the exhaust than usual. However, after a little search here i just attributed it to the extreme cold weather.

2. About couple of weeks ago, i took her out after a week or so of inactivity. I got to my destination, switched her off and the engine oil light came up for few seconds. So off i went to the dealer to pick up some top up oil. As recommended by dealer i bought:

Went home topped it up the next morning. I should have took her out for a quick spin right away but with all the snow i decided not to. I let the engine run for couple of minutes only. Fast forward to yesterday now i am getting a lot of vibration during idle and check engine light comes on after few minutes. Did a quick coolant check and this is what it looks like now:

Which isn't very good at all. So planning on flushing the coolant system. Did a quick engine oil check as well:

Not sure if this is how it is suppose to be??? The dip stick indicates the oil level is fine. I don't think the head gasket is blown else i think the temp indicator needle will point towards the red. I am actually tempted to take the car in for proper servicing. I have a feeling the independent dealer i bought the car from didn't actually service the car as he said he did. The car service indicator is saying 4k before next service but not sure if this is oil/insp.1/insp.2? Has anyone here had similar issue? If not any idea what could possibly be causing these issues?

Thanks…

 

[alfamale]

Sounds like O2 sensor, if it's solid yellow light it's ok to drive, just don't rag it
Mines booked in for a new one next week £400 that includes the initial diagnostic, the new sensor and fitting
It's a bit steep but I want it done at main dealer as I have only had the car a few month

Happy Christmas to all

 

[mmm-five]

That's the only indication I had of my problem - which in my case resulted in a new engine & ancillaries.

 

[SGRG]

Thanks alfamale and mmm-five for the quick response. I certainly hope it doesn't require a new engine!! Although the car is under AA warranty 5 star cover so should worse come to worse it should be covered.

 

[mmm-five]

Thanks alfamale and mmm-five for the quick response. I certainly hope it doesn't require a new engine!! Although the car is under AA warranty 5 star cover so should worse come to worse it should be covered.

I wouldn't worry - these engine are quite reliable, and I assumed it was just an O2 sensor when I called BMW Assist - but by the time their 'technician' had spent 30 minutes revving the nuts off it to 'clear the fault', I think the damage had already been done.

 

[paddy wright]

Could be a coil pack

 

[alekos911]

Please define rough idle..as I see nothing wrong with your idle in your video( except for the eml light) I hear no strange noises and the engine speed is stable and no oscillating . To be honest though i would be super anxious about the color of your coolant. Just a thought.. Was your engine overfilled with oil?

 

[SGRG]

Please define rough idle..as I see nothing wrong with your idle in your video( except for the eml light) I hear no strange noises and the engine speed is stable and no oscillating . To be honest though i would be super anxious about the color of your coolant. Just a thought.. Was your engine overfilled with oil?

I should have described it better, when i say 'rough idle' I am not referring to the instrument gauge alone but the car in general. Only way i can describe it is when i am sat down on the driver seat it feels like i am sitting on a massaging chair on the lowest/intermittent setting maybe? I can definitely feel the vibration and i know it isn't normal as it never use to do it before. Regarding the engine oil, i did check the dipstick before topping up and it was towards the lower end. I topped it up with a litre of oil from BMW dealer. Does the oil pic look normal at all?
I am not sure if you should be able to clearly see oil there.

I am definitely concerned about coolant as well. I am thinking of just taking in the car for servicing as one is due in 4k anyway. Any idea if i book the car in for inspection 2 the dealer will diagnose the issue as part of the service? Also do inspection 2 include coolant flush or is that extra? Apologies for the endless questions this is my first bmw.

Thanks fellas

 

[alekos911]

Look when I start the car from cold...yes I feel a slight vibrtion when the engine speed drops to normal. I am not worried about that as my father's 911 also does that and my coolant is definitely nothing like yours. I guess that is why the oil is still cool and it needs some time to adequately lubricate all parts. Also because of the sporty orientation of the car..the engine bushes cushion less ''vibrations''. But despite all that ,when the engine is warm it is super smooth.

 

[mmm-five]

Look when I start the car from cold...yes I feel a slight vibrtion when the engine speed drops to normal. I am not worried about that as my father's 911 also does that and my coolant is definitely nothing like yours. I guess that is why the oil is still cool and it needs some time to adequately lubricate all parts. Also because of the sporty orientation of the car..the engine bushes cushion less ''vibrations''. But despite all that ,when the engine is warm it is super smooth.

Don't forget that different engines have different characteristics, so just because a lumpy idle is standard on one car, does not make this the correct operating mode for another car.

For example, my e34 M5 had a lumpy tickover as standard due to the way it was designed and the cam profiles it used, and had a pronounced 'rocking' as it sat there - almost like a misfire.

My Z4MC did not have this characteristic, so when it started exhibiting this lumpiness I instantly assumed something was wrong.

I don't believe any of the sixes in the e85/86 line are meant to have this lumpy idle.

 

[alekos911]

Its hard to quantify (does this term exist?? ) "vibration" through a pc screen... I just said that engines when they are cold especially the first 2-3 minutes tend to operate a little (just a litte) ''roughlier'' than when they are up to perating temperature.

 

[SGRG]

Could be a coil pack

Paddy you were right on the money! Coil pack and spark plug for cylinder 1 had to be changed.

Took it to BMW Colchester and got it sorted for £77. Car runs fine now.

Got the break fluid and coolant changed as well but damn dealer didn't even stamp the service book. So will have to go back and get that sorted out. Bit worried about the coolant though. The dealer supposedly did a coolant flush today but when i got home and checked the coolant it is still brown.

After coolant change today (see first post for before pic):


Any chance some of you wonderful people can take a picture of their coolant reservoir and post it here just so i know what it should look like exactly and also use it as leverage at the dealer?

Cheers