Chrysler Repair: 1995 New Yorker runs bad and gas smell, diagnostic capability, o2 sensors

Question
When I 1st start the car and drive it it is fine. After I stop someplace and then start it back up it will not accelerate and I get a gas smell. It's not missing, and the tranny is not slipping, it just bogs down. After a few seconds of giving it gas it will start to pick up and runs ok up to about 45 mph. It will sometimes run 55 mph. Also the mpg has dropped from 22 to 15. It has already had a tune up and the O2 sensors replaced, but that didn't help. Fuel pump and filter were replaced 6 months ago.

It seems like it's getting too much fuel.
Any help or advice is greatly appreciated.

Answer
Hi Gary,
Take advantage of the self-diagnostic capability, using the ignition key:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the check engine light, which remains 'on', to see it begin to flash, pause, flash, etc. Count the number of flashes before each pause. Then repeat the process to be sure you have an accurate set of flash counts. Then tell me what they are using a 'follow-up' question. We'll go from there.
In the meantime, check under the hood when you smell gas to see if you find any sign of a frank fuel leak around the fuel supply/return lines that come into the engine compartment on the passenger side of the engine and attach to the fuel rail that runs around the top of the engine to feed each cylinder. Also mention whether you have the 3.3 of the 3.5L engine.
Roland