Picking the car up from the shop tomorrow - symptoms here: https://www.northamericanmotoring.co...reads-yay.html

They replaced the Vanos solenoid connector (could have been the problem) and the downstream O2 sensor (which should not cause a slight idle stumble at start up, but what the heck). We'll see how she runs - I have ordered the PCV membrane kit from ECS and will do that myself.

To the point - threads here indicate a nasty throttle body could cause an idle stumble - Pelican Parts has a very good set of instructions for removal on their site, so I'll follow that.

Has anyone done the procedure? What did you clean it with? Any noticeable driveability improvements? Thanks!

 

FWIW - I have a 2009 MCS. At ~ 130K miles, had a hunting/stumbling idle. For me, issue was caused by PCV hose that runs from rear passenger side of valve cover to intake. It's a plastic hose with a mesh sheath over it. It had a slit in it which the mesh sheath covered up perfectly.

The above issue occurred after I had replaced throttle-body. Oh, I was able to source a replacement PCV hose from rockauto for like $22.

Good luck!

W

 

Thanks, I saw that yesterday - will get one. So far it seems the replaced faulty Vanos connector and (maybe) the bad O2 sensor corrected the stumble - temp dropped last night, so I'm going to take her for another ride in a minute.
Ordered the PCV membrane fix from ECS - hopefully that, a new PCV pipe, and a clean throttle body will ease the excessive oil burning.

Aggravating that you can get an aluminum replacement VDO throttle body for the R56 convertible but only plastic for the hatchback - from the pictures they do not look compatible. I comprehend the wonders of modern materials science, but over time with that much heat it seems reasonable to assume plastic engine parts will warp or deform. Would be nice to have an aluminum valve cover, also.

 

Well, the new O2 sensor and Vanos connector did not fix the stumble at idle - going to clean and possibly replace the throttle body and install new PCV hose (new diaphragm already installed). New VC gasket 12000 miles ago along with new Vanos solenoids - also burning oil about a quart every 600 - 700 miles.

Love the car but it is an every day commuter and needs to be reliable (especially after all the work done the past 3 years).

Will prob keep her and just send the cylinder head out to be reworked if all else fails - another 1500.00 . In the meantime I will prob just plunk down 15000.00 for a new little gas saving commuter - Ford Fiesta or some such - not a fan of buying new but I'm about ready to let a warranty take care of some of this sh#t.

 

Also- Mods, thanks for moving this but mine is a 2nd generation, not 1st.