PRESSURE REGULATING VALVE

[Southernboy]

Has anyone come across this item as a problem in the past. I went out this morning, cranked the motor...it turned over, gave a hiccup, and then started, but there was a cyclical "snort" as it turned over...also it wasn't turning over very smoothly...it's item # 2 in the diagram below.


What has happened, is the upper section above the "inverted cone" has split, allowing the engine to suck air in through the break. This unit balances the engine pressure between the upper and lower ends...The one hose goes to the cylinder head area, and the other to the crankcase...
For future reference, this part is available ex Meyle at a considerable discount compared to BMW.... £.48.50 vs £.70.34. (includes 14% VAT)
Replacing it requires removal of the intake manifold and the ancilliaries to get that out...so not a 5 minute job.
I'll post a pic of the offending damage when I get the old part out for those who might like to know where / what / why etc...

[Southernboy]

3 hours to strip and assemble. New part fitted, and all well again.
This is the part that was damaged....

[Robert T]

Good info, Barry. Looks like another rubber item that perishes with age - any idea which models have this? If you're at the stage of replacing rubber hoses, then I'd have thought that this little beastie won't be far behind in needing to be replaced.

Cheers R.

[Southernboy]

The orange part you can see, is a diaphragm...it is waht is housed inside the black plastic circular casing...the black casing has been popped..and split... The plastic was very brittle....I'm not sure which other models have these, but certainly on my 1997 2.8. The part # is 11151703484. It's actually held onto a bracket under the throttle body by three M6 bolts. One hose links into the dipstick tube at it's base near the sump entry point, the other hose clips onto a nozzle at the tappet cover...and a third point attaches to the bottom of the intake throttle body...so it would seem there is a connection to upper and lower engine areas, as well as the throttle body...the third connection point is directly behind the orange diaphragm. It has a rubber collar which slides over this nozzle you can see in the pic, and which slots into a hole under the throttle.

[Southernboy]

The saga continues.....
yesterday I replaced the above regulator...and to complete the task I loaned a small torque wrench from my mechanic...so this morning I drive off to return his tools, and my car is running beautifully again...I get to his workshop, and have a cuppa tea and a chat...then start up to set off again, and my car cuts out 100 meters up the road...I crank it and eventually it starts...I turn around and by the time I get back to his workshop it has cut out again...He puts the diagnostics onto it and Error 65...Cam Position Sensor...!!!
After being told that it requires dismantling all manner of stuff to get to the sensor / connector etc etc...I decided to leave the car with him...he can do this one...I did my mechanic thing yesterday..enough already for me!!
(Fortunately he had a SAAB 9005 which he has loaned me for the interim...)
He did suggest that the above regulator may have been damaged as a result of a backfire into the intake manifold, which may have been a consequence of the faulty Cam sensor...which leads me to say, one really needs to follow the service manual carefully to ensure that parts are replaced as advised...they have an "estimated" life and as in my case, it would seem it has cost me a new regulator when a replacement cam sensor would have saved the damage to the regulator.
The joys of aging cars...might be time to upgrade...Z4 M Coupe...?