My girlfriend's 1985 240 Wagon (with 300,015 miles!) typically runs very smooth and silently. A few days ago, she went to start it, and the car ran very rough...almost like it's missing, the engine bucking a bit on it's mounts...won't settle down to an idle. It will keep running if you feather the throttle and kind of keep giving it some gas, but the throttle response is somewhat delayed. If you take your foot off the gas completely, it will stall.

So, I unplugged the AMM, and the car starts and idles perfectly. But if you give it more gas, it kind of hesitates, but will hold revs if you hold the throttle in a steady position. If I take my foot off the gas, it will idle perfectly.

My question: Is the AMM bad, or can I try one of the many methods mentioned on this board to clean it? Which method is safeest/most effective? And, should none of these methods work, where can I get a good AMM for the best price? Could I be misdiagnosing this problem? If so, what am I missing?

In the process, I am also going to clean the throttle body since it's probably not been done in quite some time.

Things I know are good, and have been replaced in the past 10K miles: plug wires, plugs, cap, rotor, belts, flame trap, fuel pump relay, 25A fuse under hood, fuel pump fuses, and a few other things that now escapte me.

Thanks in advance!!

Aaron