Dons digifant has idle control electronics in the ecu and not a separate module as we see in the wbx. The idle control valve, that humming vibrating item in the intake system is very similar between the digifant i4 and the wbx.

As to troubleshooting a low idle, Bentley manual for golf, Jetta, 89-92 has a rundown. If it was me, I'd start by cleaning connections, cleaning out the idle valve ( the hummer), double checking timing, disconnecting O2 sensor,

Alistair

> On Dec 22, 2014, at 9:26 AM, Stuart MacMillan <stuartmacm@GMAIL.COM> wrote:
> 
> Beats me, but that would be far more sensible than the separate unit in a wet area like the Vanagon.  Except, of course, that means he needs an ECU to swap in to find out.
> 
> Stuart
> 
> -----Original Message-----
> From: Neil N [mailto:musomuso@gmail.com] 
> Sent: Sunday, December 21, 2014 7:57 PM
> To: Stuart MacMillan
> Cc: vanagon@gerry.vanagon.com
> Subject: Re: Isolating an idle problem?
> 
> Does Don's engine use an ICM?  I don't recall Digifant on the 8V inline engine having that as a separate part. I think it's part of the ECU.
> 
> Neil.
> 
>> On 12/21/14, Stuart MacMillan <stuartmacm@gmail.com> wrote:
>> 
>> Idle control module,.... Try to find
>> an ICM to borrow for testing, they are expensive. It's mounted way 
>> behind the right tail light.
> 
>> 
>> -----Original Message-----
>> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On 
>> Behalf Of Don Hanson
>> Sent: Sunday, December 21, 2014 8:43 AM
>> To: vanagon@GERRY.VANAGON.COM
>> Subject: Isolating an idle problem?
>> 
>> I've been seeing an intermittent low idle-sometime no idle with my 
>> Digifant
>> 84 van 92 rabbit/fox/Jetta ecu, etc.
> 
> 
> --
> Neil n
> 
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> 
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> 
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