i currently drive a 2002 renault fiji megane 1.6 petrol engine car recently it has started to judder and jump when driving along it almost cuts out on changing into lower gears at roundabouts and juctions no codes show up on machine i have replaced coil packs spark plugs all of them filter map sensor idle sensor 02 sensor and most recently the throttle positioning sensor my mechanic says it cant be the fuel pump as it would cut out all together and we are both stumped has anyone else got any ideas HELP
