Question regarding plenum removal - The Unofficial BMW M5 Messageboard (m5board.com)

huntercross · 11th October 2008, 20:42

I am going to take my plenum off in the next couple of days to try to clean out the idle control valve (my idle fluctuates a bit) and replace the throttle valve switch. (is there 1 or 2?)

My question is, do I need to replace any of the plenum or throttle body gaskets when doing this? Also, any insight to cleaning out the idle control valve or replacing the throttle switch would be appreciated.

J Irwan · 12th October 2008, 20:10

Quote:

Originally Posted by huntercross

I am going to take my plenum off in the next couple of days to try to clean out the idle control valve (my idle fluctuates a bit) and replace the throttle valve switch. (is there 1 or 2?)

My question is, do I need to replace any of the plenum or throttle body gaskets when doing this? Also, any insight to cleaning out the idle control valve or replacing the throttle switch would be appreciated.

I think depend on the condition of the rubber gasket. If it is deteriorating then you should replace it.
On mine I did not replace mine as the intake plenum gasket still in good condition (when I replaced the "fuel tank breather valve" under the plenum).

Regardz,

J Irwan

mfizzlenyc · 12th October 2008, 23:11

From what Ive read and done you must replace the gasket upon removing the plenum

J Irwan · 13th October 2008, 00:25

Quote:

Originally Posted by mfizzlenyc

From what Ive read and done you must replace the gasket upon removing the plenum

That would be depend on the condition and the mileage.

My beast had around 36K when I removed the intake plenum, the rubber gasket still pliable and solid.

This intake plenum gasket (sandwiched between the top and the bottom intake plenum) does not see as extreme heat like say "Valve cover" gasket or "head" gasket.

If you ever open the valve cover, I would alway replace that.

Although one thing I forgot mentioned to the OP. There are 16 "self-locking" nuts that should be replaced (self-locking nuts ideally to be used only once).
These are the nuts that secure the original (8) Air intake funner/trumpet to the lower/bottom intake plenum.

My $0.02

Regardz,

J Irwan

everycredit · 13th October 2008, 21:58

You "should" replace it, but you may not "need" to repace it.

Don't use gasket in a tube stuff. Recoat with glycerine to prevent friction from putting the cover back on and prevent tearing. Glycerine can be in suppository form, personal lubricant, or Mr. Bubbles. Pick whatever is most convenient and least embarassing.

huntercross · 14th October 2008, 01:12

Quote:

Originally Posted by everycredit

Glycerine can be in suppository form, personal lubricant, or Mr. Bubbles. Pick whatever is most convenient and least embarassing.

Hahahaha!

Thanks for all the input. Does anyone have any tips for both cleaning the idle control valve and replacing the throttle valve switches?