I have done a slew of troubleshooting & replaced several things over the last 2 months. Here is the list:

new plugs, cap & rotor, plug wires
new fuel pressure regulator
new fuel filter & pressure checked by Volvo shop
cleaned throttle body & new gasket
checked idle air control motor
New O2 sensor in the exhaust line (however the splices I made are loose)
removed the injectors & had them tested & cleaned at Dr. Injector (specialty shop in Seattle)
new filter sock on tank fuel pump
removed CAT & checked for loose stuff - all ok
all of the Bentley section 241 electrical checks are OK
Timing, idle & mixture set by Volvo shop
swapped in another used AMM which gave different problems so swapped mine back in
This second shop (see below) adjusted the valves today

I now have it at the second Volvo shop & he is having difficulty setting the mixture. The instrument he is using (sorry I don't know exactly what it is but he is reading various things including the ECT output) this instrument has him disconnect the O2 sensor and adjust the mixture at the AMM. He said they typically set it for 0.6 % CO. On my car he cannot get it that low, it tends to be more than 2.0 % CO.
He is wondering about the fuel injectors (however they were removed, cleaned and balanced - so I'm assuming they are good).
Is there something else that could cause high CO, with little ability to adjust it down?
He also said the adjustment on the AMM seems to be working fine and it cannot be my bad splices for the O2 sensor because it is disconnected.

It does have the LH 2.2 system which I have heard is pretty robust.

Other thoughts?

Thanks

Mike

--
1988 245, 237K mi, 5 speed