I've got an '07 Cooper S (R56/N14) and recently got the CEL and dreaded P1497 code. When the engine is running, you can distinctly hear a loud hissing sound. When I shut the engine off, the hissing continues for a good 10-15 seconds.

I just replaced the Valve Cover Gasket, mainly because that was an inexpensive and simple fix to try. Hissing is still there.

I know everyone says the valve cover could be the culprit, but, the weird thing is, it almost sounds like the hissing is coming from UNDERNEATH the intake manifold, instead of on top where the valve cover is.

i'd rather not spend $350 for a new valve cover, especially if that's not the problem. I'm happy to try different things, but I'd rather not just keep throwing money at the engine.

What is underneath the intake manifold? Specifically, what is under there that could be hissing?

I checked for snakes... no snakes.

Help!!

 

The wastegate vacuum valve and reservoir are under the intake manifold. Might take 10 - 15 seconds to bleed off if there's a leak in that system.

 

Forgive my ignorance, but when I search for "wastegate vacuum valve", I get varying results from "Turbocharger Wastegate" to "Brake Booster Vacuum Valve" and I'm assuming those are not the same things.

Can you be more specific (speak loudly and slowly [wink])

 

They are NOT the same. Take a look at the illustrated parts list for the wastegate hoses --- they connect both the reservoir and "valve" (I forget the actual name of this control) --- http://www.realoem.com/bmw/enUS/select

 

Crack in the valve cover itself

https://www.northamericanmotoring.co...1497-code.html


For those other noises:

https://www.northamericanmotoring.co...ing-off-2.html

&

https://www.northamericanmotoring.co...-manifold.html



Here is the diagram,

https://www.realoem.com/bmw/enUS/sho...82#11657599547

#2 is the pressure converter, #1 is the vacuum tank that connects to the wastegate.

 

UPDATE: Ended up buying a new valve cover, because I was still seeing oil all over the top of the cover after replacing just the gasket. After putting in the new cover... VIOLA!! The loud hissing sound is gone!!

Sounds like it was the valve cover all along! Lucky for me, it was easy enough to do myself. saved on labor cost, at least!!