I have changed out the idle stabiliser unit with no effect. The injector
spray patterns are a little beyond what I think I can do in the street in
front of my house, what with the environmentally-correct neighbors casting
their glances in my direction and talking amongst themselves about the
obsessed guy always trying to tune up his d**m Vanagon.

What would running a tank of premium tell you about the engine? Carbon
buildup in the heads? I did run two tanks of 89, just to see, but there was
no apparent effect.

On Thu, 18 Jan 2007 10:54:21 -0800, jon <jon@KENNEKE.COM> wrote:

>G-
>
>I'm not a 1.9 expert...however, you haven't mentioned messing
>with the injectors nor the idle stabilizer control unit. Either one could
>cause you problems.
>
>Try running a tank of premium(!).
>
>Jon (The 2.1 FI Guy)
>
>> The stumbling idle on my '84 1.9 is driving me nuts. No matter what I've
>> tried, with and without the help of the goodly folks here on the list,
>> nothing has helped. New O2 sensor with good ground, tested good on car.
>> Compression 155-155-145-130. No oil burning, no coolant leaks, no smoke,
>> plugs all textbook-beige. New dist. cap and rotor, new fuel pressure
>> regulator, new fuel filter, new idle switch tested good, rebuilt AFM, AAR
>> removed/cleaned/tested good in freezer and warm stove (car starts fine.) No
>> vacuum leaks--vacuum tests around 13 inches, and I've pulled the vacuum
>> lines time and again to check--all of them, even the ones at the AAR.
>> Removed, cleaned throttle body, sealed at inlet, no light shines through
>> butterfly valve. Changed oil, used Marvel Mystery in hopes that would help
>> lifters if they were air locked. Used Seafoam to get carbon out of cylinder
>> heads. Changed bad thermostat. Checked all grounds and built ground "web" to
>> all points in engine. Checked battery voltage at startup and running (over
>> 12.5). New cat, new muffler, new rear engine mounts.