Date: Sat, 4 Sep 1999 00:22:47 -0700
Reply-To: Coby Smolens <cobys@WELL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Coby Smolens <cobys@WELL.COM>
Subject: Re: Digijet ecu failures, "Bosch - Bosh?"
In-Reply-To: <3.0.1.32.19990903235452.006b5190@pop.mindspring.com>
Content-Type: text/plain; charset="iso-8859-1"
First thing I'd do would be to check the harness from the main plug at the
control unit per Bentley diagram/charts. You can check every component in
the system from the plug. Add to this a test for short-to-ground through
every wire not intended to be a ground. It is important to do this BEFORE
installing another control unit, whether for test purposes, or a new or
rebuilt one. We don't want to fry a nice new $500 part, now do we?
The next step would be to install a KNOWN GOOD (NOT new or rebuilt - the
idea is that a new part is not known to be good) unit for testing. I'd say
it's extremely unlikely that you've got four bad injectors. More probable is
that ONE of them shorts internally to ground, so be sure to check for that
while you're measuring resistances (i.e. measure R between each injector
contact and the case of the injector). I don't really think that's where the
problem lies, though - the injectors are actually insulated pretty well from
ground contact by the seal, the nozzle cover and the big rubber hold-down
ring. The spec for injector winding resistance, measured through the wiring
harness from the CU plug, is 16-16.4 Ohms. (Terminal location for injectors
at the plug as follows: Hold the plug horizontally, looking into the
terminals, with the cable exiting the plug on the left. Terminals are in two
rows. Upper row, left to right is #1 - 13. Lower row, left to right is #14 -
25. Injectors are at terminals 11, 12 23 and 24 on the plug. Terminal 7 is
the common ground for all four injectors.)
The "new-isn't-known-good" thought brings up an interesting point, which
should actually be the subject of a post all by itself, entitled "Bosch?
Bosh!" or something like... In fact I'm adding it to the subject line now -
see?
The scuttlebutt regarding Bosch is that there may have been a major problem
with quality control for a while there and that we are seeing the results of
this breakdown as the parts which rolled off some production lines are
finally hitting the shelves. I heard this from my sales rep at H&H
Distributors after I sent back two rebuilt SR17X starters in a row with bad
drives fresh out of the box. She told me that Bosch fired their quality
control director and replaced him with a woman (sorry I don't have her name)
who is whipping things into shape, but that we could expect to see some
returns until bad batches are uncovered by hapless techs and consumers like
me and you. Comforting thoughts, eh? Please be advised that this is
hearsay - I have no proof of these allegations. But they WOULD help to
explain a few mysterious multiple failures. Like new ECUs? Like new
injectors.
If you're dealing with non-Bosch rebuilts the above won't necessarily
account for your troubles, although my own experience with the FI
aftermarket reman scene is such that I flatly refuse to install ANYTHING
from Bret or Python. The only person who gets their hands on my CU repairs
these days is Darrell Boehler - a member of this list - who is a highly
meticulous and careful person who goes all out to test his own work before
returning it to you.
Good luck AND happy hunting...
Coby
Valley Wagonworks
"Intimately acquainted with VW Vans since 1959"
Volkswagen Bus, Vanagon, Westfalia and Eurovan
Repair and Service Specialists
1535 Sir Francis Drake Blvd., San Anselmo, CA 94933
Voice:(415) 457-5628
Fax: (415) 457-0967
http://wagonworks.com
mailto:contact@wagonworks.com
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM]On Behalf
> Of Bill Thomas
> Sent: Friday, September 03, 1999 8:55 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Digijet ecu failures --- Help !
>
>
> I have the same problem with my 83.5 Digijet. My Westy is sitting dead in
> the driveway with full-on injectors again about 300 miles after ECU was
> rebuilt. Could not find fault with the harness when checking for shorts
> while flexing wiring.
>
> Injectors read 8 to 10 ohms resistance. One source listed about
> 16 ohms as
> spec. These are new Bosch injectors installed last year - possibly
> defective and causing the ECU components to overheat?
>
> Looking for answers. Any clues out there? Eager to get my Westy
> dependable for the cool Fall weather approaching but do not want to be
> stranded in the back of beyond.
>
>
>
>
>
> At 08:44 PM 9/3/99 EDT, you wrote:
> >My '84 Westy with the Digijet fuel injection has just blown another ECU.
> >The third in 6 months! I havent had the chance to thoroughly
> check out the
> >wiring yet but something must be causing this. The van runs faultlessly
> >between failures. When they go the injectors are locked open
> so there must
> >be a path directly to ground as the injecters are modulated to ground to
> >operate.
> >Has anybody else had these failures with the Digijet model?
> What did the
> >solution turn out to be ?
> >Any help will be greatly appreciated. Steve
> >
>