Thanks to all of you here for the advice that has turned me from a 240 owner to an enthusiast. After years of trouble free service my wagon developed some issues. Bad idle, severe hesitation starting from idle. The check engine light has been on for quit some time (2 years maybe) but did not seem to effect performance. I have done the following in the last month

replaced fuel pressure regulator
cleaned throttle body and idle air control
cleaned ground contacts on the fuel rail
removed temp compensation board in gauge and connect pins 1 and 3
inspected all hoses especially corrogated between AMM and throttle body
found O2 sensor
unplugged and inspected electrical connections at AMM, IAC, each injector, throttle position switch (does click when going off idle), and block temperature sensor (under # 3)
One tank of gas with techron concentrate

Results: great idle, little to no hesitation, but check engine light has returned after reset with codes indicating lean/rich. I suspect rich as exhaust fumes are strong when I get out of the car after a drive across town. However my gas milege is fine (23+ on highway)

I am planning on the block temperature sensor as my next fix.

Any thoughts or suggestions would be appreciated.

Randy