[FR33K]

Hi all. Over the last few days I noticed a bit of a popping sound from the exhaust on gear change which I thought was a bit odd. Today I felt my car acting a bit funny so I pulled over and the idle was all over the place from revving to 3k down to nearly stalling. Popped the hood to find that my oil filler had come off ??? Anyone had this problem ?? How do i get it back on ?? And why would it be causing a rough idle ?? Mods are only stage 1 APR and Forge Replacement BOV. Thanks for your help!

2009 2.0T

 

[brittan]

I believe that the filler cap neck is a tight push fit into the cam cover. I'd clean up both mating surfaces with white spirit or similar degreaser and roughen them with fine wet/dry paper. Block the hole so you don't get any bits into the engine.
Then I'd use a liquid metal adhesive or something like Loctite Bearing Fit to re-secure the filler neck.

The rough idle is because the engine breather system directs the fumes into the engine inlet tract. With the cap missing the engine is sucking in air via that open hole and this air flow is not being measured by the MAF so the engine is getting more air than the ECU 'knows' about and hence the air/fuel ration is incorrect and the lambda sensor will report incorrect oxygen level in the exhaust back to the ECU.

I'd also dump the BOV.

 

[FR33K]

Thanks for the info ! As for the BOV.. cannot get that off soon enough !!! Driving me nuts lol

 

[mr gee]

There has been some suggestion in other forums that this may be signs of the PCV valve not working and allowing excessive pressure in the block. How's your oil consumption btw?