When engine cold no problems. When warm, engine stumbles from idle (700rpm) on accelaration in neutral & 1st gear, all other gears stumbles upto ~1200 rpm on accelaration. I'm running 94 octane & tried fuel injector cleaner through the tank (mild temporary improvement) & done the throttle body with an aerosol cleaner. I can't find any air leaks. What next? I'm thinking maybe IAC valve or plugged cat? Car has 125000km & had the 'big' service done at 100k by dealer. I have noticed that the fan cycles on & off at ~1 minute intervals almost as soon as the car is started way before it gets to operating temperature, not sure if its related. Any thoughts/suggestions appreciated.
Gavin.