Z4 Fluctuating rev, rattle and misfire

[Lytesben]

So my first week of Z4 ownership has not gone well at all. Got in the car yesterday morning and started it up fine, then realised the revs were fluctuating. It then sounded like it had a bit of a misfire and the EML came on.

I thought maybe it might be the MAF at first but unplugging that may almost no different if maybe a slight improvement. I've plugged it in and it has thrown up the following codes:

P0102 - Mass or volume air flow - circuit low input

P0113 - Intake air temperature - circuit high input.

On starting it this evening it is again fluctuating revs and there is a rattle coming from the top of the engine

View: https://youtu.be/PPu2UVA17_w


Anyone able to help point me in the direction of what's wrong? Starting to wish I never bought the car!

 

[billz]

Have you not got any codes showing. Is the rattle from within the rocker or outside of it. If it is outside then i would suggest the water pump. If it is in the rocker then i would presume there is an issue with the cam shaft, maybe a lifter gone

 

[Lytesben]

Have you not got any codes showing. Is the rattle from within the rocker or outside of it. If it is outside then i would suggest the water pump. If it is in the rocker then i would presume there is an issue with the cam shaft, maybe a lifter gone

Yes, I've mentioned the codes above. I'm guessing that either water pump or cam shaft is going to be expensive?

 

[oldcarman]

Don't panic yet, I don't know z4's but many on here do and will be along shortly with what to check for. Hopefully it's something fairly simple so good luck! JIM

 

[MAURICE THE MARTIAN]

Another possible cause could be the vanos
They can rattle similar to that .if it is that
They do sell a kit with seals and anti rattle springs .
Hopefully you can get it sorted .
M

 

[raymond]

Probably the vanos. Don't run the engine if possible.

 

[jamie_z4]

Sounds like the disa valve to me?

 

[Lee]

Sounds like the disa valve to me?

I would start here too. best to start with the cheaper options.

 

[jamie_z4]

also Disa valve failing would give your symptoms.

 

[t-tony]

Just hope it hasn't broken up.

Tony.

 

[Lytesben]

So got around to removing the disa valve this morning to have a look at the state of it. Took it out and it looked absolutely fine, put it all back together and it now seems to run perfectly again and no rattling.

So I'm guessing that something was wrong with it and taking it out and refitting has fixed it

 

[oldcarman]

If only it was always so easy, glad it's running right now! JIM

 

[raymond]

Great news you have managed to fix it. Keep an eye on the water level and the oil. The plastic thermostat housing is prone to failure. Check the cars receipt's to see if it has been replaced.

 

[jamie_z4]

Good stuff I need to check mine