no offence but really cant see that amking 148 releastically.
im running a 130 spec 1.8 in my mk4 and that will not make 148 if its life depended on it and thats a rebuilt engine with no egr so identical mods to yours apart from cam timing is standard setup and no chip. just cant see why you would get that much gain the timing being changed and just a chip?
in regards to it stoppingcheck that the EDIS plug is all the way in as mine cut out once, couldnt work out why then found the EDIS plug was a little backed out so was causing it not to spark.