I need some help troubleshooting a problem. Lately my car, a 91 240 auto, has picked up a really bad low idle and a tendancy to die at idle. Origionally it would just run high during warmup and once warm the rpms would drop to 1500 but the whole time it would run really rich. If the car was turned off and restarted the idle would be really erratic. If I stepped down on the gas pedal the car would die on the spot, if I simply took my foot of the brake the car would move foward like normal, and if I just lightly touched the gas pedal the car would slowly accelerate. If I managed to get the car up to about 3500-4000 rpm, usually in second gear, the car would run normal afterwards and I could step on the gas but it would still idle high. None of this info is valid if the car was in neutral or park, in which case I could rev it all the way to 6000, but it would have no effect on drivability. To take care of the issue I've replaced the plugs, rotor, and cap. I have also removed the throttle body and completely cleaned it and adjusted the throttle position switch. I did get ohm readings at wide open and at closed. I also removed and cleaned the throttle control valve and check for continuity on it. Also within the last 500 miles the AMM and the alternator have been replaced. Now that all this work has been done its all over the board. I started up the car after the claening and it idled perfectly at 900 rpms, even sounded better then new. I decided to head for a drive to conduct an errand. Car drove perfect for the first 15 miles then it started to loose a little power for a moment but surged right back to normal and drove fine for the rest of the way. On the return trip I started the car and the idle was hovering around 400 rpms, but drove off just fine with plenty of power. Hopped on the highway and the car started to loose power again, the harder I pressed the gas the more power it would loose. Then another surge and the car drove fine for another mile before starting to dye again. Hopped off the highway at the first available exit that would get me home. At any stop the car would idle at 400 rpm and kept trying to die. Only solution was to put the car in neutral, step on the gas to keep the idle up, and then shift into drive when the light changed. By the time I got back to campus even this wasn't working and the car would stall any time I stopped. I disconnected the throttle position sensor and that didn't help, same with disconnecting the AMM. But after a dozen stall I mangaed to get it parked. This morning it drove fine with everything plugged in until the car was warm then it was back to its tricks. I need lots of help on this one, I'm on a student budget so troubleshooting is the best place to start and I can't keep replacing everything in the hopes it will solve the problem. But at this point I'm starting to think the best cure is a stick of dynamite, and long fuse, and a good head start. Sorry for the long read but I figured the more info the better the chances. -Russ