Date: Tue, 18 Apr 95 12:05:27 CDT
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: Joel Walker <JWALKER@ua1vm.ua.edu>
Subject: Re: Air Flow Meter and Idle/Mixture Adjustments
On Tue, 18 Apr 95 11:10:58 CDT Donald Baxter said:
>I have an '85 Vanagon with 135,000 miles on it. It runs really well but the
>idle and mixture adjustments are concerning me. It barely passed its
>emissions test this year and probably won't next year--I would prefer and
i think david (or whoever) is right: check the oxygen sensor. you can get
them at FLAPS for about half of what vw wants (you'll have to put your own
connectors on the wires).
>EXCEPT that now when I let off the accelerator the idle does not return to
>normal immediately -- 4-5 second delay -- Sometimes longer.
that is pretty normal, i think. it's the oxygen sensor controlling things
again. the computer on these Digijet and Digifant EFI systems seems to be
very sensitive to the sensor (oxygen sensor, coolant temp sensor, etc.) input.
the older L-Jetronic analog system was much easier (imho) to fool with. maybe
not as pollution-free, but easier.
>Anyway, I am assuming that the Air Flow Meter adjustments have little or no
>effect on this engine. Do I need a new Air Flow Meter (or perhaps
>rebuilt)? Will a new AFM make any difference in the amount of garbage I
>spew out the tail pipe?
i doubt that you need a new AFM. if it was bad, you'd have all sorts of
running problems, not just emissions. i'd replace the oxygen sensor if you
don't know how long it's been in there. and be SURE to get the right type
of paste/sealant/anti-seize!! the wrong kind can ruin your sensor in very
short order! the right kind says "safe for Oxygen Sensors" or some such.
Then, dcarment@ccs.carleton.ca (David Carment), said:
>BTW it is normal for there to be a delay in idle drop. 4-5 seconds is not
>abnormal. DC Since we are in the topic: is there anyone who can convince
>me that the full throttle switch actually does something? DC
i've been to chicken to rev the engine that high. :) but i do know that the
idle position switch does affect the fuel supply (on digifant) by cutting
off the fuel to the cylinders when you take your foot off the throttle going
down the highway. and if the switch is badly adjusted, you can have idling
problems.
joel
