Hi 

I have a Nissan Micra Tekna lgt 1lt 99BHP

when it’s cold it stutters through the Rev range between 2400-3600 rpm more noticeable in 3rd gear. When it’s warm it’s either very slight or not noticeable. Has anyone else, it’s been back to the dealers twice and they said they did notice a slight judder once but couldn’t get it to repeat but they only did 2 mile so not much of a test drive. Any help appreciated Thanks John

it could be many things, breakdown in the electrical/ignition system, throttle sensor, coolant sensor, air mass meter.....it really needs a scan when driving it and recording any instances that it may occur.

You can use a device call a Data or Flight Recorded and review the info afterwards to see when it is occurring and what parameters changed at that time