Date: 31 Jan 97 11:38:49
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: Karl_G_Vochatzer@notes.amrcorp.com
Subject: Re: trying some new timing settings...
Donald wrote:
dbax @ mindspring.com ("Donald Baxter")
01/30/97 07:02 PM
To: vanagon @ lenti.med.umn.edu (Multiple recipients of list) @ Internet
cc: (bcc: Karl G Vochatzer/AMR)
Subject: trying some new timing settings...
I have been having problems with steady idle, intermittent, and
usually after the van has been running at high speed for at least 30
minutes. At idle, the van will rev up to around 1400--1600 RPM and
then drop down to normal, slowly rise again and then drop back down.
I replaced the coolant temperature switch for the ECU, and this
seemed to fix the problem for a week or so, only to have the
condition return.
I have generally set my timing a little bit advanced (I think this is
advanced--mark to the LEFT of the engine seam). I tried setting the mark at
the
seam for a few days and the van seemed be unusually sluggish and the
idle problem was much worse. I tried setting the timing last weekend
back to the left again, only a bit further. Idle problems have
completely disappeared--idle is much steadier than even the times
when the condition was less apparent. The van is noticeably more
powerful--especially on the low end, but also maintains 70 (and even
higher) on the freeway very willingly.
Side benefit is also the first time my van has EVER reached 21MPG in
urban cycle driving.
So what are the nasty side effects of timing my van this way? Maybe
the pulley is marked improperly?
BTW, I filled out a brochure request on the Passat web site for the new
European mode--the book showed up at the office
today--looks really nice, especially interested in the new 110HP TDI
engine.
Donald Baxter
'85 GL Vanagon
>>>
I have the same idle hunting problems on my 88 GL only mine are much more
pronounced.
- typical warm engine idle is around 1500 RPMs
- occasionally it will idle at 950-1000, but more commonly 1500
- cold weather idle is between 2000-3000 until warm and then steady at 1500
- quite frequently the warm engine idle surges from 1500 to 2500 then drops
back down to 1500 only to surge back up to 2500 and drop back down, etc.
I have cleaned all the electrical connections I could find in the engine
compartment, but not the ground straps. I've cleaned the throttle, the inside
of the air filter container, used fuel injection cleaner in the gas, and
installed new plat. plugs (according to records new wires, new fuel injectors,
fuel filter, the "wire harness", and a new ECU was installed about 20K ago). I
have also checked the idle stabilizer for anything obvious looking, but I
haven't replaced or borrowed a "good" unit for testing. I hadn't heard of
changing the timing for this symptom, but it sounds like Donald may have
discovered something here. However, my Vanagon runs superbly otherwise, and
averages between 18-20 MPG consistently.
Anyone care to give detailed description of timing a 2.1 wasserboxer (or
re-post an existing description) if this seems to be the way to treat the
symptoms?
Thanks,
Karl 88 GL