Date:         Mon, 11 Mar 1996 08:48:07 PDT
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         "Shawn Wright, SMUS Network Analyst" <swright@smus.bc.ca>
Subject:      Re: '88 lurching at 2500-3000 rpm

> On Fri, 8 Mar 1996 18:19:45 -0600 you said:
> >Drove the new baby to work today - first time in some traffic - and
> >noticed some lurching in 2nd & 3rd gear at around 2500-3000 rpm. ie:
> >trying maintain a steady speed in slow traffic would result in a
> >surging or lurching motion. Accelerate to a little over 3000 & it
> >would mostly go away.
> 
> hmmmm. this might be a worn circuit board in the air flow meter ... the
> little wiper arm eventually wears through the coatings in one or more
> spots (it kinda depends on the habits of the previous owners). a cheap cure
> is to remove the lid of the air flow meter and carefully bend the wiper arm
> so that it "wipes" a new path across the printed circuit. this has been
> successful for several people. then you have to glue/seal the lid back on.
> 
> joel
Well, after much coaxing with a big screwdriver, I got the top off. 
Sure enough, there was a well worn groove in the dark grey coating on 
the board, and a couple parts were quite deep. I spent half an hour 
wondering how much it's going to cost me to replace this thing when I 
screw it up beyond recognition, then went at it with some needle nose 
pliers. Amazingly, a quick twist on each side of the copper arm 
seemed to do the trick, and moved the path about 1mm closer. A quick 
test drive seemed to show improvement, and today's drive to work 
confirmed it. The lurching is still there, but much less pronounced.

Is the contact board material supposed to be almost black? Should it 
also be cleaned with alcohol as someone in the archives suggested? 
(The parts were clean, but there was a slight amount of "black dust" 
along the edge of the trace.)
Does the seal on the airflow cover have to be airtight? I resealed 
with silicone, but had damaged one corner a bit getting it off...

How do you adjust the idle? Mine is at about 1100rpm & surges from 
1000-1250 or so regardless of temperature. I'm thinking this may be 
another cause for the surging - is this likely?

Thanks!
*--------------------------------*
| Shawn Wright, Network Manager  |
| St. Michaels University School |
| 3400 Richmond Rd, Victoria, BC |
| Canada                 V8P 4P5 |
| (604) 592-2411 Fax: 592-2812   |
| swright@smus.bc.ca             |
*--------------------------------*
I haven't lost my mind;  I'm sure it's backed up on tape somewhere!