my 1998 626 4 cyl. idles roughly and stalls when warmed up,seems to hesitate like its flooding when i accelerate.someone mentioned a bad smell when following me a couple times.i have no cel light coming on.cleaned maf and iac valve.could this be the catlytic converter?if so what could happen if i keep driving.thanks

 

When my wife's Saturn blew the cat, it rattled internally. It idled fine and didn't stall, but would not accelerate well and the temp gauge went higher than normal.
The "brick" in hers gave out, but yours may be clogged or clogging. This can be caused by excessively rich running over time or oil, or other contaminates being burned (carbon?) in the engine.
If the cat turns out to be the problem, expect to replace the O2 sensor at the same time.

 

my car does the same thing i have a 93 escort Gt with the Mazda BP DOHC cam 1.8 5 speed i replaced the fuel pump, filter Vane Air Flow Meter, TPS, IAC, temp sensor, oxy sensor, "EVEN THE ENGINE WAS REPLACED" and the dam thing still starts and runs like it starves for fuel or is floodin out my next step is to eather replace the ECU or delete my Cat Converter or it could be a bad coil

 

Pull a spark plug or two and see if it's a light tan color. Black or wet plugs indicate rich mixture, misfire, high tension issues etc. etc. Rich mixture can cook out a catalytic converter.
The most probable cause though is in the fuel supply area. Check charcoal canister for excessive fuel content, all electrical connections OK, fuel pressure OK, fuel main and return lines clear, no leak in pressure regulator etc. etc.
The rotten egg smell also indicates high sulphur content in the fuel, that's not a car issue, its a gas station issue; try using a different brand.