On Sat, Oct 23, 2010 at 5:49 PM, Scott Daniel  - Turbovans
<scottdaniel@turbovans.com> wrote:
> It will be interesting to see if this 'fix' sticks.
> I'm mildly skeptical..
> but ..hey ...if those problems are now gone ..
> that'll make me a believer.
> just never ran into it anywhere ever.

Yes me too. The way I see it, with the engine it it's stock position
in a Jetta, those wires wouldn't be so close to the high tension
leads. But meh. Who knows?   :)

> I think it's semi-normal almost for one of your engines to have an uneven
> warm idle....when miles are high.

Well to be clear, when engine up to temp, restarted, idle wanders
up/down for about 5 seconds, then idle is steady. No misses. Just
wanders. This seems worse in really hot weather. Engine supposedly now
has ~ 120,000 KM's.

> I'd go for things like intake leaks..
> worn valve guides or seals,
> carbon deposits on the top side of the intake valves ..
> things like that.
> I never hear of it anymore ..
> but when such cars where newer ...shops would clean intake valves in place,
> fairly often.
> Even blasting with walnut shells.
> Supposedly BMW and Chevron worked together on the gasoline formulation when
> that was a problem back when.
> in any case...for uneven idle I would be thinking about everything to do
> with 'air' ..

This is why the IAC code being thrown made sense to me.

IF interference from high tension leads was affecting power to/from
the idle air control valve, would this affect it's behavior?

> engines are just air pumps after all. They're like an air pump driven by
> internal combustion that also drives �pistons downward � ..but it is all
> about air flow ..particularly about smooth warm idle.
> Scott
> ----- Original Message ----- From: "neil n" <musomuso@GMAIL.COM>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Saturday, October 23, 2010 5:15 PM
> Subject: WAS: OBD Reader.... NOW: High and Low Voltage Wires. Problem
> Solved??
>
>
>> Hi all.
>>
>> Since my laptop code reader stopped working, I went old school and used
>> OBD1
>> blink codes. I found ECT and VSS as before, but also IAC (idle air
>> control)
>> and CMP (hall sensor on dizzy) �Whaaa?
>>
>> Seems the related wires were too close to the ign. coil high tension lead
>> (Pic: �*http://tinyurl.com/3xse3mj �) *allowing interference from high
>> voltage leads to leak into these wires. Repositioned wires, wrapped new
>> ECT
>> wires with tape, no more codes.
>>
>> Bonus: This may also cure the CEL intermittently lighting up, and brief
>> idle
>> hunt when restarted hot. It may be that hot weather exacerbated the high
>> voltage leak.
>>
>>
>> Neil.
>>
>>
>>
>> On Wed, Oct 13, 2010 at 9:59 PM, neil n <musomuso@gmail.com> wrote:
>>
>>
>>
>>> Any recommends on an affordable but thorough code reader? Using Ross Tech
>>> freeware I found this DTC: "Intermittent Short To Ground Coolant sensor"
>>> DTC. I need something for the engine management that is that thorough.
>>> For
>>> lack of a better term.
>>>
>>>
>>
>> --
>> Neil Nicholson '81 VanaJetta 2.0 "Jaco"
>>
>> http://tubaneil.googlepages.com/
>>
>>
>> http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engines
>
>

-- 
Neil Nicholson '81 VanaJetta 2.0 "Jaco"

http://tubaneil.googlepages.com/

http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engines