M54B25 in a Z3 - Very Rough Idle, INPA Screenshots

[KI4UJO]

Ok, I know this isn't exactly a Z3 forum, but r3v is normally pretty useful, so help me out here. My dad drives a 2001 Z3 2.5. As of a few weeks ago, he began to notice a loss in fuel economy and a rough idle. Now, the car will barely idle(attempts to stall) , but does seem to run ok once you are above idle.

Upon discovering these issues, I went ahead and replaced the CCV with the upgraded cold-weather version. There was oil present inside the intake, but it did not solve the issue. Also, I replaced the plugs with a set of NGK BKR6EQUP.

My current thought: VANOS seals (car has 250K, it realistically couldn't jurt to replace them anyway)

Any ideas? He needs this to drive to work, so I realistically need to get it figured out quickly.

1 by Jonathan Martin, on Flickr

2 by Jonathan Martin, on Flickr

3 by Jonathan Martin, on Flickr

[sublimation]

Maf?

[328ijunkie]

MAF/Vac leaks still

[KI4UJO]

I found a valve cover gasket leak, so I've got one on order.

[KI4UJO]

Replaced the gasket, but the issue still unfortunately persists.

[KI4UJO]

Solved: it had a defective DISA valve (O-Ring was bad,along with the vacuum actuator no longer functioning)