Revs playing yo-yo

[BarryPr]

G'day All,

Between say 80 and 100 km/h the revs drop then go backup. It is intermittent and it is a pain in the proverbial.... The drop is sometimes small and sometimes not so small.

Has this happened to anyone of you or maybe a mates car? Any ideas?

Thank you.

 

[CocoPops]

Hey Bud,

Maybe a bit more info would be helpful to diagnose problem:

Is it under load?
FReewheeling?
When braking?
Loss in power?
year/mileage etc..

Im sure this would help the guys who would be able to help you.

Sweet..

 

[Nikhil]

Is it an auto?

 

[BarryPr]

OK.

Auto, 530D 2003 E39 270k.

The noise is when accelerating only. Once she is up to speed it is still.

Thanks.

 

[Low N Slow]

airflow metre:=):

 

[BarryPr]

airflow metre:=):

OK cool. I suspected the MAF. Only one way to find out. I will unplug it over the weekend and see how she goes.

Thank you.

 

[RAArmstrong]

Torque converter isn't locking up... Sounds like its time for a gearbox recon... Though I may be wrong :fencelook:

 

[BarryPr]

Torque converter isn't locking up... Sounds like its time for a gearbox recon... Though I may be wrong :fencelook:

The gearbox has been recond already.

Anybody know of a good bmw technician here on the West Rand (Gauteng).? I live in the Krugersdorp area.

Thanks.

 

[BarryPr]

An update on this issue which is still not resolved.

I found this:

http://www.bmwland.co.uk/forums/viewtopic.php?f=4&t=148541

The one person said he had the same and replaced the DISA gasket.

I looked into it a bit more and it seems this gasket can be the cause.

Will my car have something like this? :sorry: For asking but I know nothing of engines.

Thank you.