[s-cars] STILL fighting ignition problem

[Brian Powell]

Thanks to all who responded last week on ways to test my coil packs.
To revisit, I have hesitation (misfire) under boost. I have new plugs
and coil boots. I tested the coils with the spark gap tester up to
about the 42,000 volt mark and all coils sparked similarly (if
sporadically) at that length (around 1"). I then tested the resistance
of the coil packs themselves (thanks S. Eiche), and they are all
within reason at ~13 MOhms.

So, by both tests, all coils are performing similarly. Thus, what
next? I look to the POS. Possibly, the POS isn't allowing enough
through to create a spark? The POS failure has been reported to be bad
under boost in rare cases.

My wife has a 96 A4Q (12v V6) which has a POS (strange system: only
one POS for the V6), but built by Hitachi not Bosch. The part number
for the POS on the A4 and the POS for the S6 is the same, but, the S6
has an "A" appended and (as I said) is made by Bosch. Both have a 3
wire and 4 wire connectors with the same wiring layout.

My first question is: can I swap in the A4 POS to use as a tester for
the S6 without blowing the Hitachi?

Second, any other suggestions for a high boost (20+ psi) misfire?

Thanks in advance.

-- 
Cheers,
Brian