newbie with problems

[greener]

Hi there
I bought a mk3 8v and I need some help/ideas.
It ran for a couple of weeks then started cutting out then completely died.
I've changed the distributor,  throttle body, crank sensor, plugs and leads, even tried a different ecu and fusebox in it but it still wont work, it will start then it will rev and dip then cut out .
I really like the car and dont want to get rid, anybody got any suggestions.
Cheers

[gazareth]

hi can you here the fuel pump running when you put ignition on?

[greener]

Hi
Yeah have good fuel flow

[gazareth]

could be the cat broken up. does the exhaust note sound any different recently?

[greener]

Oh rite, yeah did sound a bit different

[gazareth]

try taking out your lambda probe and start it. does the car idle properly?

[greener]

It idles for about 30 secs then revs and dips then cuts out

[gazareth]

do you mean it revs on its own then cuts out?

[greener]

Yeah it revs by itself then dips then revs then cuts out

[gazareth]

hi what year is the car? and do you know if its an agg or a 2e engine that's in it?