hybrid 1043 Report post Posted July 19, 2009 Been having some funny issues for some time with throttle response in the car under loading. About 2 months a go I lifted the bonnet of the car to hear a god aweful rattling sound coming from the manifold. A bit of research showed my 'Adjuster Unit' / DISA Valve had given up the ghost. Symptoms include: below average fuel consumption, Under heavy or full acceleration load torque hesitation. A very loud rattleing sound when the hood is up. Here is a video brendon and I did on the difference between a worn one and the new one. The new revised one has better wearing properties and a better soleniod. And a quick install vid. Part Nubmer: b11617544805 List price: $612.64 :| (use the bimmersport JC discount to reduce this) Engines effected: m54b30 Here is a bit of info on the flow dynamics of these engines. This is the airflow circuit diagram for the intake; the green is the Idle control circuit, and the purple is the intake air circuit: The following shows Low RPM airflow with the DISA valve closed: The following shows High RPM airflow with the DISA valve open: And the DISA valve in person: Quote Share this post Link to post Share on other sites
hybrid 1043 Report post Posted July 19, 2009 Forgot to add. Its a good idea at this stage to do a full reset of the DME trims and may as well reset the EGS trims at the same time. It is not essential to do this but will help the maps with the odd airflow it recieved around 4k. Quote Share this post Link to post Share on other sites