Adrian:

Sorry for the late reply, but I read digest mode....

If you have the harness fix, it is not "Vanagon syndrome,"
which only happens on the highway after a long steady drives.

 From my experiences with a Digitool, I suggest that you
check the O2 sensor carefully.  In my 2.1 '87, after a
warm restart, it seems that the ECU/O2 pair don't like to
start working together until the throttle switch has been
punched.  Before that, it loves to bog down or stall unless
reved up.  (Sometimes....)

Punching the throttle means the throttle switch.  If the O2
sensor is working correctly, then maybe it is just a "feature"
of your ECU.

                                Richard A Jones
                                Boulder, Colorado