Hello,

I've written a couple of posts about my van's deteriorating idle.

(1994 *or 95* ej22 in 1982 A.C. vanagon)

It's always had a sticky idle, but now it's gotten unbearable. Lately it's
been starting at 3500 rpm and sometimes staying there. It's rarely below
2000 rpm anymore. it will occasionally settle down to 900 and act normal.

after 15 minutes driving in town, the CEL comes on and the idle drops way
down, big loss of power. I'm convinced it's a vacuum leak - just feels like
it. Exactly the same conditions as when brake booster hose came off - minus
the hard-braking.

Today i finally ordered a replacement gasket for the IAC.

On Monday, i'm taking it into my mechanic's shop where he will be restoring
the spare -tire tray, which was displaced at time of conversion.

I'm going to pull the IACV before the van goes up on the lift... clean it,
inspect the rubber boot etc.

BUT, before I work on the IACV, I want to check out the TRANSMISSION ID
wire.
(I suspect that there are multiple problems with my van's idle)

On the printed OBD1 pin-out chart, terminal B48.20 is listed as the
Transmission ID.

Do I understand correctly that this identifies if its MT or AT, and it
would affect the vehicles idle. If my engine and ECU came out of an AT
Legacy, I would want to reassign it as an MT.

Is this a matter of grounding or ungrounding B48.20?

I really want to see what this does, before beginning on the IACV.