Did valve cover gasket replacement, now no vaccum pressure

BlueSander · 11-09-2021, 01:19 PM

Hi guys,

So long story short, I did my valve cover gasket replacement toward end of last year during Covid. Pretty much during my first test drive, I got the following error code:

120308 - Charging pressure control, Plausibility Pressure too low

Changed out a bunch of stuffs, including the Boost pressure Solenoid, the code is still there. Today, I finally realized that there isn't any vacuum pressure coming out of that outlet on the side of the Valve cover to the Boost Solenoid. I found this after seeing the Wastegate not moving while pushing the throttle. Anyhow, I think there is a good chance I cracked the valve cover while taking it out. Will prob do smoke test this weekend. In the meantime, if anyone else has experienced something like this, please let me know. Much appreciated!

95blkmax · 11-10-2021, 07:47 PM

Quote:

Originally Posted by BlueSander

Hi guys,

So long story short, I did my valve cover gasket replacement toward end of last year during Covid. Pretty much during my first test drive, I got the following error code:

120308 - Charging pressure control, Plausibility Pressure too low

Changed out a bunch of stuffs, including the Boost pressure Solenoid, the code is still there. Today, I finally realized that there isn't any vacuum pressure coming out of that outlet on the side of the Valve cover to the Boost Solenoid. I found this after seeing the Wastegate not moving while pushing the throttle. Anyhow, I think there is a good chance I cracked the valve cover while taking it out. Will prob do smoke test this weekend. In the meantime, if anyone else has experienced something like this, please let me know. Much appreciated!

Smoke test into the crankcase would expose a crack in the VC assembly. Also a whistling noise at idle. Check for cracks in the Vac pump to VC hardline. Also that the o-ring on the VC 90* connector isn't simply rolled.

If you end up needing a VC assembly, check JDMSpeed on Amazon. They sell it for about $95. They have a great reputation on the N55 group in FB for the last 2years+ that people have been running it successfully with zero QC issues. I've been running mine almost a year and love it.

Cpazza69 · 12-21-2022, 04:14 PM

Hey, did you manage to resolve this issue? I too have just replaced my valve cover gasket and now have the charge air pressure control issue.

I am thinking I should replace the entire valve cover now. Would you agree?

11-09-2021, 01:19 PM	#1
BlueSander First Lieutenant 68 Rep 382 Posts Drives: M550i Join Date: Mar 2008 Location: CT iTrader: (0)	Did valve cover gasket replacement, now no vaccum pressure Hi guys, So long story short, I did my valve cover gasket replacement toward end of last year during Covid. Pretty much during my first test drive, I got the following error code: 120308 - Charging pressure control, Plausibility Pressure too low Changed out a bunch of stuffs, including the Boost pressure Solenoid, the code is still there. Today, I finally realized that there isn't any vacuum pressure coming out of that outlet on the side of the Valve cover to the Boost Solenoid. I found this after seeing the Wastegate not moving while pushing the throttle. Anyhow, I think there is a good chance I cracked the valve cover while taking it out. Will prob do smoke test this weekend. In the meantime, if anyone else has experienced something like this, please let me know. Much appreciated! Last edited by BlueSander; 11-09-2021 at 02:45 PM..
	Appreciate 0 Tweet Quote

12-21-2022, 04:14 PM	#3
Cpazza69 Registered 0 Rep 2 Posts Drives: BMW F11 535i Join Date: Dec 2022 Location: Houghton regis iTrader: (0)	Same issue Hey, did you manage to resolve this issue? I too have just replaced my valve cover gasket and now have the charge air pressure control issue. I am thinking I should replace the entire valve cover now. Would you agree?
	Appreciate 0 Quote