94 jeep grand cherokee misses when cold

94 JGC misses under acceleration when it is cold, or in the warm up mode...usually disappears after 15 minutes of driving. Comes back after engine has sat for a couple hours. Misses at about 1600 rpm, and after it has warmed up it occasionally misses around 2700 rpm or more. Replaced the fuel filter, cam and crank sensor, and has had a complete tune up, including new plug wires, but problem still persists. 3 different shops, no one can seem to pinpoint the problem...any direction which way to head with this??

First thing I would do is to check the fuel pressure just to make sure the fuel pump is working correctly. Check it when it is running right and when it is missing. Could be a number of things a bad or weak fuel injector a bad cat converter partly pluged egr could be a weak coil. Does the problem get worse when it rains? Iam leaning more to the coil but the coil usally gets worse when warm. You might want to try this when its Dark get a spray bottle of water and start the motor and spray around the ingition system to see if there is any arcing. Just a few things to start with.