CAR PERMORMANCE

I HAVE A FORD ESCORT 1.6i YEAR 2000 X REG WHICH HAS DONE 63,124 MILES.
JUST RECENTLY I HAVE HAD LOSS OF POWER WHEN DRIVING AND THE CAR 'JUDDERS' WHEN
IDLING. IT STARTS STRAIGHT AWAY AND THERE IS
NO FLUCTUATION OF THE NEEDLE ON THE REV COUNTER. WHEN DRIVING, IF I TRY TO EXCELERATE BY PUSHING DOWN PEDLE, THE CAR STUTTERS AND THERE IS NO POWER. ALL SPARK
PLUGS HAVE BEEN CHANGED AND THE LEADS LOOK OK.