OOPS!
Big screw on the throttle body!

John Rodgers
88 GL Driver

John Rodgers wrote:
> Did you adjust the idle speed screw on the AFM?
>
> You seem to have covered everything else. I didn't see it mentioned on
> your list.
>
> Warm the engine - run it around the block.
> When back home - disconnect the idle stabilizer valve wire on the end of
> the valve.
> Start the engine.
> Turn the very large slotted screw on the AFM. Turn right or left and
> watch the tach. Remember your start point when doing the adjustment. I
> count the screw flats - 5 right, or 10 left or whatever.
> When idle speed settles at 900 rpm you are good enough. Reconnect the
> ISV wiring and you are good to go.
> Allow the engine to get cold, Restart. The cold start should give you
> about 1200 rpm, and after it warms up it should drop back to 900-1000
> rpm for idle.
>
> Regards,
>
> John Rodgers
> 88 GL Driver
>
>
> Tim Marciniak wrote:
>> Has anyone had an idle stablization control valve that hummed as
>> Bentley describes it should, but found that after replacing it their
>> idle problems were solved?
>>
>> My van idles at 1200.  Runs fine, starts fine.  But I cannot get it
>> to idle below 1200 rpm.   I have spent hours trying to figure this
>> thing out.  Here's run down of what I've done.
>>
>> -complete ignition tuneup, plugs, plug wires, new distributor cap,
>> checked timing
>> -cleaned all ground connections and replaced all ground connectors
>> -replaced temp sensor x2
>> -found open circuit from temp 2 to terminal 10 of ECU.  I replaced
>> this wire.  I thought I had all my problems solved when I found this
>> and in fact it did fix a lot of my idle issues because prior to this
>> fix I had even more driveability issues.
>> -adjusted and checked throttle position switch
>> -cleaned idle stabilzation control valve with carb cleaner and
>> verified that its humming away.
>> -cleaned throttle valve
>> -new O2 sensor
>> -checked fuel pressure--ok
>> -no vacuum leaks
>> -checked air intake system, verified that I had no false air issues
>> -replaced idle stabilization control unit (this is the last thing I did)
>> -passed state emission test two weeks ago
>>
>> Van runs smooth, no lumpy idle, no hesitation or surging issues, just
>> idles high at 1200.  Only thing I can think that is left to do is
>> replace the idle stabilization control valve on top of the engine.
>>
>> Tim
>> 90 Multivan
>>
>>
>
>