Does your '83.5-'85 digijet idle roughly when cold?  I had gone though checking
for vacuum leaks, bad sensors, installed a DigiTOOL and discovered the culprit
to be a bad Aux Air Valve.  Installed the replacement today and my westfalia
starts and runs so smoothly now.

Roughly here are the procedures I followed to replace the valve.

1.  Remove the air box assembly.

2.  Remove the AFM.

3.  Remove the plastic intake elbow.

4.  Remove the vacuum lines and electrical connection from the Aux Air Valve.

5.  Using a 10mm socket on a 1/4" drive with a 6" extension (3/8" will not
allow the socket to mate to the bolt properly) remove the 2 bolts attaching
the the Aux Air Valve to the right head.

6.  Reverse the following procedures and reassemble.

7.  Go to the front and start the van.

8.  Listen in amazement as the idle is nice and smooth rather than a rather
than an offensive chug chug.

Hope this helps some others.

Jason M Yasment
'84 Westfalia
Troy, NY
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