Help!
Problem: WHen car warms up it starts running very rough, then stutters, then eventually stops. After a few times acting like this it will not start again for a few hours.
I have noticed the following things:
fuel milage guage jumps all over when it idles rough
when it actually runs, it stutters when I rev (not when cold but gets worse as motor warms up)

WHat I have done:checked timing belt..looks new and timing is correct
checked plugs-no carbon..seem to be burning properly
changed distributer cap and rotor

The T-shaped air flow thing just off the intake valve (?) has a little dry rot crack in the rubber.

Not sure where to start--fuel pump, o2 sensor, injectors

someone told me maybe catalytic converter is bad?

Thanks for your input I am at a loss as to next step.

I thought I was a pretty good mechanic..but feel stupid right now!

Rock

disconnect o2 sensor

disconnected the sensor wires,,,no change, started and ran for about 10 seconds very rough...then died. now won't start. looked in bentley manual...thought maybe fuel not right so I pulled out dipstick to simulate lean condition...still no good.

I don't have a meter to check plug on o2 sensor. guess I need to.....

observation--after sitting a few minutes it tries to start and run. after this it won't start....acts like it is not getting fuel ???

try to run pump manually- jump fuel pump relay

Yeah...doing that tonight. I think it is relay, pump, or filter.

jumped relay..pump runs fine. I am going to replace the relay.

Run it until it dies. Immediately open the gas cap and if there is that "chhhhhhhhh" sound like lots of pressure relief then the tank may not be venting. Fuel pump will not be able to pump if the tank is depressurized too much.