£1600 Z4 2.0i Misfire :S (Video)

[jonneyboi]

Hi All,

I just purchased a Z4 as abit of a summer toy..

When I brought the car it was running ok, there was a code for a bad MAF and it did feel under powered however I was hoping the MAF would fix the issue.

I purchased a new MAF (Cheap one from eBay I have genuine replacement coming) and it appears to be working in that I'm getting readings using my OBS2 reader however the car still isnt running right. Yesterday it developed a misfire on cylinders 1 and 4.

The car is idling horribly as hopefully the picture will video will pickup, does any one have any idea what it could be? or could guide me on what to look for / test? http://www.youtube.com/watch?v=kxYKNF25M0U

Also bit of background the guy I brought it from did mention that it failed its last MOT on emissions and he ran 'BG products' (engine cleaner) through the engine which sorted it. The mot tester mentioned it could need a new catalytic converter.

Any advise would be appreciated... hopefully the car isnt a complete gonner

Heres the link http://www.ebay.co.uk/itm/232333656226?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT [/url

 

[andyfanshawe]

Hi.
Good postings with live data! But, is this at idle or not?
Can your scanner display graphs?

Would like to see what the o2 sensors are doing while driving. In graph mode.

Where in the country are you?

Golden rule with maf sensors is go genuine if you can.
Personally I would fit a proper maf, then go for a test drive and monitor all o2 sensors in graph mode, and all short term and long term fuel trims.

Can you feel the misfired?

Any variable valve timing engine is very sensitive to the oil being clean and perfect. If there is any service holes in the book, put a forte oil flush through it and put some good oil in.
I use mpm bmw oil through a local motor factors ( minorfern) in my 06 2.0 z,4 and it is running well.

Let me know whereabouts you are please.
Andy

 

[Chris_D]

Hi.
Good postings with live data! But, is this at idle or not?
Can your scanner display graphs?

Would like to see what the o2 sensors are doing while driving. In graph mode.

Where in the country are you?

Golden rule with maf sensors is go genuine if you can.
Personally I would fit a proper maf, then go for a test drive and monitor all o2 sensors in graph mode, and all short term and long term fuel trims.

Can you feel the misfired?

Any variable valve timing engine is very sensitive to the oil being clean and perfect. If there is any service holes in the book, put a forte oil flush through it and put some good oil in.
I use mpm bmw oil through a local motor factors ( minorfern) in my 06 2.0 z,4 and it is running well.

Let me know whereabouts you are please.
Andy

andy, whats ur forte oil flush method?

and whats ur thoughts on this stuff - forte oil fortifier. had a bottle sitting around for ages. meant to use it on a 250k mile M52 engined 3 series coupe but wasnt experiencing any problems so decided not to explore the bold claims it makes....

 

[jamie_z4]

as a side note i never knew they did a z4 with a manual roof

 

[jonneyboi]

Hi.
Good postings with live data! But, is this at idle or not?
Can your scanner display graphs?

Would like to see what the o2 sensors are doing while driving. In graph mode.

Where in the country are you?

Golden rule with maf sensors is go genuine if you can.
Personally I would fit a proper maf, then go for a test drive and monitor all o2 sensors in graph mode, and all short term and long term fuel trims.

Can you feel the misfired?

Any variable valve timing engine is very sensitive to the oil being clean and perfect. If there is any service holes in the book, put a forte oil flush through it and put some good oil in.
I use mpm bmw oil through a local motor factors ( minorfern) in my 06 2.0 z,4 and it is running well.

Let me know whereabouts you are please.
Andy

Hi Andy,

Thanks for the reply..

All the readings are from about 30 seconds after start up on Idle. Unfortunately I don't think my scanner does graph mode although I have ordered a new bluetooth one which should. In regards to the o2 sensor they are fluctuating between 0.02 volts and 0.7 volts, which I think I normal? On concerning thing is the STFT are pegged at 0, which I think could indicate an issue??

I can certainly feel the misfire the car is very underpowered and constantly feels like its about to cut out. Given the condition of the car I wouldn't have thought it was too well looked after. I have just ordered some forte flush so will give it a go on Friday and report back.

Thanks again for the tips, and I live in Epsom, Surrey.

Jonathan.