Mother-in-law has car problem. Starts, then put in gear and dies.?

Idle speed motor could be defective, but first of all I'd check the vacuum lines on the top of the motor. All the 6 cylinder Jeeps are prone to drying out and cracking of the vacuum line connections for the PCV valve, and some other associated vacuum devices. There is one that runs from the top of the valve cover over to the intake and it is prone to plug up with crud, particularly on engines with higher mileage. Great engines, but because they are still basically a very old design from the 60's they are prone to some blowby gases that clog this line up with a little age. The obvious other stuff as well such as fuel pumps and such are also possibilities, but most of these Jeeps that I have seen have been simple problems. In 2000 the fuel filter is actually on the top of the tank and the fuel pump assembly. To change it you drop the tank. Wierd design, but a friend of mine got well over 150,000 miles out of his and never did have to change it so much be a good enough system. :-) One other idea is that they also have crankshaft sensors on the bell housing that are prone to failure. Usually this will cause the vehicle not to spark and start after turning off, but can cause similar troubles to what you described. Two bolts hold it on at the top of the bellhousing on the transmission just behind the block. Have to get to it from underneath, but with a small wrench, or a few socket extensions is easily changed.

IAC Motor...Idle Adjusting Control Motor. If it ran well before that would be the place to start. If it ran badly before then you might have a vacuum leak. Also could be the Vacuum brake booster...is the brake petal hard to push?

It has multi point fuel injection

just get rid of the mother in law, and problem solved

HAS THE BATTERY BEEN REPLACED? OR GONE DEAD? IF SOTHE ECM HAS LOST ITS MEMORY SHE WILL NEED TO START THE VEHICLE AND KEEP THE ENGINE IDLE UP FOR ABOUT 2 TO 3 MINUTES SLOWLY LETTING UP ON THE GAS PEDAL IS THE CHECK ENGINE LIGHT ON? IF IT IS THAT WOULD BE A COMPUTER CONCERN. IF IT HAS A THEFT DETERANT IT MAY BE THAT.

a chum of mine had a motor vehicle like yours and it become the sensor that runs the torque converter.does you motor vehicle have a lock-up converter?if so verify the sensor.they circulate each so often on them grand ams.your grinding noise may well be a wheel bearing.

soooooooooooo - you say I can converse through IM with you but how do you propose I do that.

So what's the problem?

J/k

sounds like your manifold air pressure sensor.{M.A.P.}