Van starts idles ok but when revved up a few times the engine is then rough

Forgive my ignorance but how do I check for a plugged cat convertor

first try hitting it with a rubber hammer to see if you can hear anything rattling,then you can either get an emissions test done or disconnect the converter to see if you have more power...

Thanks only prob is cat is part and parcel of the down pipe but will try your advice

unless you have already changed it I would check/change your fuel filter and check your fuel pressure because its easier to do than a converter...

Thanks have a pressure gauge on its way to test the fuel system did have a problem with the pump in the past

did you change the fuel filter?

Not yet but plan to its not too easy to get some parts here in the uk

it says your from tacoma wa

I don't know why it has done that I'm in Salisbury England

they do that all the time and I dont know why either.. but now that we established where you are from did you get a fuel filter for it ?

There is one on the way, as is new cap, rotor, plugs and wires . got someone to climb the revs at idle didn't seem as if there was a lot coming out of the tailpipe. will have to work my way through your suggestions and hopefully come up with a solution as I love my Chevy .