I had someone ask me about an idle problem on Fox once. I did not know
anything about the car, I just knew Rabbits. I looked under the hood
and I could not see an idle pseed adjustment. They went to the dealer
and they bumped up the idle speed. I have no clue where they did that
as I have not worked on a VW Fox yet. I am a shadetree mechanic for me
and an occasional friend.
On Sat, 13 Sep 2008 20:22:37 -0500, "dave AKA vwdoc1"
They hid that adjusting screw from you huh! SHAME on them!!
Some of them might have had an anti-tamper plug on them. I have not seen
one of those plugs in soo many years I might even be mistaken.
That idle adjusting screw should be on the throttle body just like the
Rabbits except easier to see IIRC.
Jim you do very well with the answers! I would call you a GURU! :-)
Now the OP could have other issues such as the engine is running too rich,
or the secondary throttle plate is stuck open or ????
One thing I have done on other cars like my Toyota and a Sunbird was
clean the throttle body where the butterfly valve is. PCV fumes and
oil gunk that all up. I haven't seen that issue on those older VWs as
they seem to vent in a better way. Now my TDI is another story.
Back to Dave's original air leaks idea. I use unlit propane to find
vacuum leaks. Aim at likely areas to see if the idle bumps up. Some
use carb cleaner but I am afraid of goofing up paint with that stuff.
That is funny that they were conspiring against me.
On Sun, 14 Sep 2008 20:21:58 -0500, "dave AKA vwdoc1"
Common in cars pushing 2 decades are rotting vacuum hoses. My 88 has a
bunch of vacuum hoses. Start with about 10 ft of .25" vacuum hose and
replace all that size. Then, buy to size the larger ID vacuum hoses and
replace. Don't forget the charcoal canister hose. Careful, some fittings
are plastic, can be easily cut or broken.
Temp sensor may be defective causing the vehicle to run on the rich side.
Possibly, preventing normal idle, rough running, aid with gas pedal for more
air to allow it to run.
Another similar looking sensor that controls warm-up period may be stuck,
not timing out. Thermo-time switch its called.
"Brain box", actually a bridge resistive network, has no data processer, may
be defective. Located under glove box.
Any defective/kinked wiring associated with the 2 sensors mentioned and the
"brain box" can cause similar results. Check the Bentley on how to
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