Got myself a cheap runaround, runs perfect when cold and on motorway etc, when warm and driving round town it feels like its really holding back and when travelling slowly in traffic it tries to kangaroo, also when i stop at lights etc the idle goes up and down quite bad that it tries to stall, someone has said the cat may be the problem, any ideas? any info much appreciated, thanks

 

Clean the inside of the ISCV and MAF with carb cleaner.