Date:         Thu, 26 Sep 2013 21:02:33 +0000
Reply-To:     Skip <skiplaubach@COMCAST.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Skip <skiplaubach@COMCAST.NET>
Subject:      Re: Digijet rough/wandering idle and bucking at slower speeds
In-Reply-To:  <2095708492.3436497.1380209638979.JavaMail.root@sz0094a.emeryville.ca.mail.comcast.net>
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Update:  Drove at lunch today and the engine ran beautifully.  Did notice when I drove over a rough railroad crossing that the van immediately started bucking.

My diagnosis (not validated) is either a fuel pumping interruption (from the bumps) or the ECU gets "confused" when jostled over bumps or the AFM gets whacky from the bumps.  The ride smoothed out less than 100 yards beyond the crossing.

The difference between this morning and lunchtime runnability was incredibly large.  I think the fact that runnability is not consistent is a data point.

Anyone hazard to provide a root cause?

Skip

----- Original Message -----
From: Skip
To: Vanistas
Sent: Thu, 26 Sep 2013 15:33:58 -0000 (UTC)
Subject: Digijet rough/wandering idle and bucking at slower speeds

'84 1.9L (with the 2200cc GW upgrade), digijet WBXR

Just installed the Sorensen fuel injectors (w/new seals) on Sunday.  Made in America.  On sale at a FLAPS (local A-Z).  Noticed an improved smooth idle and acceleration immediately versus my (recently cleaned OE FI's.  I had to fiddle with my idle versus the OE FI's.  The Sorensen FI is a "disk" versus the OE, which is a "pistel" type FI.  Some recent chatter on thesamba about these.

Then, I drove my Westy to work this morning.

The idle was rough and wandering, in fact the
engine died a couple of times at stoplights (started right back up,
fortunately).  Some bucking in 2nd and 3rd gear.  Wondering about a
vacuum leak, timing, O2 sensor, fuel filter, fuel pump, ECU.  I can put my
hand on the problem but never my finger...

I'm leaning toward a vacuum leak and more work on idle adjustment.

Ideas?  Thanks.

Skip