The deceleration valve bypasses the throttle plate when the manifold
vacuum is high such as when going down hill with the throttle closed or
when down shifting to slow down. This allows some air into the manifold
so that there is adequate air for the fuel leaving the injectors to
burn. The water boxers never got this part as they are designed to turn
the injectors off completely when the engine is being over driven with
the throttle closed. No fuel, so no air is needed. The only difference
between the CA and federal versions is the vacuum pressure at which the
valve opens. I don't know what problems you are having but I doubt you
need to spend money again on this part.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
Of Greg Marshall
Sent: Thursday, April 11, 2002 10:21 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Part request...

Hey there list vendors and private sellers....

I need a deceleration valve for my bus....Specifically, I need a
deceleration valve from an 80-83 california van.  It's different than
the federal model, although I'm unsure of how different it is.  Here's
the part number...

 071-133-551A  Decelerator Valve Vanagon California MT 1980 to 1983

My old decelerator valve broke, and was replaced by a local shop.  I
didn't know there was a difference at the time, and I ended up with the
federal valve.  The van is having some troubles now, and I'm trying to
first return it to stock, and then start diagnosing problems from
there..

Can anyone help me out?

I'm also curious to know what the actual difference is.  I asked the
folks at bus-boys to explain, but they just said that if it's a
california van, it needs the california part.  However, they don't have
the californai part anymore.  Any Californians on the list with access
to junkyard vans?

Thanks all.

Greg.