Chrysler Repair: Chrysler Concorde 1998 lxi Dying while driving, 1998 chrysler concorde, exhaust gas recirculation valve

Question
I bought a 1998 Chrysler Concorde LXI a few weeks ago from a private seller. It seemed to run very good, with 118,000 miles on it, but now it keeps dying on me whether I'm stopped at an intersection or just driving. When I'm on the freeway It runs excellent, but when I get off and get down to 40mph on the streets it stalls on me. I can restart it almost immediately, but last time it did it I couldn't restart it. It was turning over but the engine just wouldn't start. I had to have a tow truck come and get my car, but as I waited an hour for the tower to get there I tried turning it on again and it started just fine. So I was thinking it might have over heated, but the heat gauge in the dashboard didn't go over halfway. It also seems to die when I have the radio on. The previous owner had installed Infiniti speakers in it, so I don't know if that is causing an electrical failure or the engine is just over heating. I've checked out the other posts on this website about a code, so I did the on/off/on/off/on with the ignition and the dash read P 16 If you have any ideas what could be wrong please let me know. Thank You.

Answer
Hi Matthew,
The codes are four digit so did it read 0016? If so that would suggest there is a mismatch between the cam shaft and the crankshaft engine rotational sensors. It could be real (perhaps due to an issue with the actual timing which is maintained by the timing belt and therefor would suggest the possibility of the timing belt having slipped or perhaps is wearing out which happens when it has gone maybe 100-150,000 miles. Or otherwise I am not sure about a 2-digit P code as there are none).
The other symptom, dying at random on the highway or at a stop, may be due to the exhaust gas recirculation valve being slow in its action or sticking slightly ajar when it actually should close tightly. The stem of the valve can be lubricated with WD-40 to improve or correct that problem which is subtle and therefor often present without setting a fault code.
Finally, one of the two engine rotation sensors may be failing and when they do so it is seemingly self-correcting because when they cool down they recover their function. The codes for the sensors are P0320 (crank) and P 0340 (cam) so you might want to keep checking for codes to see if either of those appear.
Unfortunately to check the timing you have to remove the spark plug of the #1 cylinder and probe to find when the top of the piston gets to its maximum (rotating the crankshaft by hand) and then you would remove the upper timing covers on the front of the engine to see if the camshaft timing marks are where they should  be. But that would be appropriate only if the 0016 code is true. Do you have any idea about whether the timing belt has ever been changed, and how many miles are shown on the odometer? Let me know, and also tell me which size (L) engine is in the vehicle.
Roland

Thank you Roland. I'm sorry I had a typo, the code reads P1684, sorry about that, and it has 118,060 miles. It is a 3.2L V6 engine. I don't think the timing belt has been changed or not. Thank you.

The 1684 means that the battery power to the engine computer has been disconnected in the part 50-100 key on-off cycles. If you haven't actually disconnected the battery, then I would check fuse N in the power box in the engine compartment. It might have a subtle crack in its wire which opens and closes as the fuse heats and cools.
So look closely at the wire inside the fuse.
Also, check the timing belt as I described and follow the other suggestions.
Roland