Date: Sun, 20 Apr 1997 21:03:22 -0700 (PDT)
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: Earl Smith <earlsmit@islandnet.com>
Subject: 84 still smokin' along
Well, in spite of all the helpful advice from all you good folks, we still
got us a nasty problem. A potted history:
Around three months ago started having signs of a problem or four. Coolant
going somewhere. Checked it out, had head seals changed on driver side.
Then fuel consumption jumped from 27 mpg to 14 mpg. Advised to change the
O2 sensor. Changed it and consumption went back down for a for a few weeks.
Then engine began surging. It felt like ( and still does ) an afterburner
or supercharger cutting in and out. One could feel the kick. Checked all
the obvious things listed in Bently. Westy took to going down the road
trailing huge clouds of black smoke. Obviously running too rich.
Confirmed by mileage which dropped back to 10 mpg. Took it to a mechanic I
know from previous experience is good. But - he doesn't profess to be an
expert on VW. He Diagnosed a bad ECU. I replaced the ECU with one known to
be good. No improvement
More advice from you folks. Read archives on the air flow meter spring
setting. Then on April 13 (bad choice you say!) I worked the ~@#$%^&*
thing over.
1 Checked throttle position switches cold - within specs
2 Pulled O2 sensor. Filthy. Cleaned with Brakleen and electrical contact
cleaner and tooth brush
3 Checked system from multi-pin connector
- air intake potentiometer is 1K not 560 ohms
- Temp sensors both at 4000 ohms with air temp at 10-15 (don't have a
thermometer for that check)
- Air intake sensor check - ohms change when it moves but very little
- Air flow meter wipe survace cleaned and contacts bent back to create new
arc surface
4 Injectors seemed OK but passenger rear leaked a bit. (what the blazes is
the cylinder numbering on those engines. Even Bently can't figure it out)
5 Ecu well grounded to engine and frame.
6 Tightened AFM spring one notch at a time till engine quit smoking at idle.
Up six notches.
Test drive - engine: black smoke ; driver: blue smoke. Rest period to
recover from heart attack.
April 17. Replace suspect fuel injector but tested before replacing and -
passenger rear didn't leak but passenger front didn't spray the way it did
the first two tests. Thats the one I replaced.
Today, replaced temp. sensor II. Test drive: I have a vacuum gauge
mounted on the dash and at 15 to 20 inches seems OK on flat and level
except cutting in and out of some electrical /electronic controller. Can
be felt. As soon as the engine loads down either from accelerating or
going up a hill, when the vacuum drops to near 5" , clouds of black smoke.
Tried tightening the
AFM up 12 notches but engine ran rough so backed it off.
Aside from jacking up the engine cover and driving a Jetta under it, is
there any hope for this monster.
Earl from Sunny Sooke