All of the vanagons I have seen have the ECU under the rear seat, and the
idle stabilizer behind the tail light.

No big heat problems with the ECU that I can think of. But, the idle stab.
may want to be near the ambient temp of the vanagon.

I'll have to look into that more when I get into reverse engineering the
idle stab.

Jon

On Wed, 20 Dec 2006, ------------------------- wrote:

> "What confuses me if why they didn't simply put that functionality in the
> ECU???"
>
>
>         VW  Did in the Golf and Jetta 88-92.  I'm assuming there is a
> heat problem
> with this in the Vanagon, because of its location.
>
>
>
> jon wrote:
>
> >I've taken apart an early (pre-86) idle stabilizer. It appears to be a
> >pulse shaping/delay unit. It is inserted in between the hall sensor and
> >the ECU. If fact, you can simply unplug both connections, and plug them
> >together to run without. It adjusts the timing based on idle RPM, I
> >assume.
> >
> >The later units are much more complex, judging by looking at Bentley. One
> >of these days I'll reverse engineer one of those. Anyone have a dead one
> >they want to send me?
> >
> >What confuses me if why they didn't simply put that functionality in the
> >ECU???
> >
> >Jon
> >(The Reverse Engineer)
> >
> >On Wed, 20 Dec 2006, John Rodgers wrote:
> >
> >
> >
> >>Sounds good to me. Anyone working on reverse engineering that idle
> >>stabilizer control module??
> >>
> >>Regards,
> >>
> >>John Rodgers
> >>88 GL Driver
> >>
> >>jon wrote:
> >>
> >>
> >>>I have made great progress in reverse engineering AFMs, ECUs and other
> >>>funny business in the Digifant injection system. It's classic 80's
> >>>embedded CPU technology.
> >>>
> >>>I pulled apart a bad ECU to use part from to build a "sniffer". It was
> >>>interesting to see how they did it. Here is a quick explanation:
> >>>
> >>>The "brain" is a standard 6803U4PV. It's a common 80's embedded
> >>>microcontroller. Not sure what the differences are in the U4PV version,
> >>>because I can't find a datasheet on the 'net. On the CPU daughterboard
> >>>there is also a Parallel Interface Adapter, some glue logic, and a 2732B
> >>>EPROM. The version label on this one is "FAEB02 02. 02". Anyone have an
> >>>ECU open, and can tell me what their's says?
> >>>
> >>>On the main board, the interesting semiconductors are a Toshiba TA7900S
> >>>regulator/watchdog with PNP shunt transistor (BD438). Across the heat sink
> >>>is also a BD647 NPN Darlington, a Motorola TE2369 (Which I can't find,
> >>>probably a house number. Anyone know what this is?), and a BT151-500R
> >>>Thyristor. The big chip near the center is an Analog to Digital converter.
> >>>Add to that some small signal transistors, couple of op amp/comparators,
> >>>and finally a "Peripheral Clamping Array" on the input to the PIA/CPE to
> >>>condition signals.
> >>>
> >>>These ECUs make magasquirts look simple. ;)
> >>>
> >>>More on AFM spring adjustments in a bit.
> >>>
> >>>Jon
> >>>
> >>>
> >>>
> >>>
> >>>
> >
> >
> >
>