Engine cuts at low revs - any ideas why

[GTIMKiiJODE]

My mate has just bought an mkii 8v gti and the engine seems to cut out for a second when you puy your foot down. Its really annoying. After cutting it pulls ok then. It just happens at low revs. You can also feel the revs just drop a little every now and then whilst ticking over.
Any ideas would be well apreciated. Thanks

[GTIMKiiJODE]

Really struggling to sort this problem. The exaust that came on the car was not standard from manifold (stainless big bore) so i firstly advised him to change this back to standard which he has done. Amazingly this cured the problem for a couple of days but now its started again. Then noticed that the engine never seemed to warm up so have put a new thermostat in so that is back to normal now (the old one fell into pieces upon removal. Have replace all of the plugs and leads, dizzy cap en rotar arm but still the engine cuts end misfires at low revs. Its a G reg mkii 8v gti. I have owned mine for 5 years now and never had any problems like this so am not sure what might be causing it. Could it be the air flow meter or coil or maybe the temperature sender. Problem seems to be worse when the engine warms up. Engine mounts are knackered as well so when engine cuts really throws engine about.

[Veedubgt18v]

check all your vacuum lines and air hoses etc on the engine, get some carb cleaner and with the engine running spray it onto suspect areas. if the engines 'bogs down' there is your leak. i used to have this on mine and i traced it to a tear about an inch long in the pleats in the air hose going to the throttle body, when i was stompoing the gas the engine would move, pull said split apart and to much air would get in and it would splutter and then sort itself out. i also had knackered engine mounts

ed

[Mirage-]

I had the same problem until yesterday when I had home tune come out and get my baby purring again at a steady idle of 850-900rpm.

He changed the leaking vacuum hose as mentioned, set the spark timing, air/fuel ratio (screw in airflow meter) and also adjusted the screw in the front of the inlet manifold.

Dunno if any of that will help but it sorted mine out.

Ian