Hi, i have a Mazda Etude (Protege) and i have been having a hard time figuring out what the problem is. The car is surging, starts jerking every time i accelerate at around 2000rpm at normal temp. But when the car is cold it runs smoothly. i changed the plugs, oil filter, cleaned the MAF, changed the fuel pump (i was told it has no fuel filter), checked the coil and leads but still no luck...please can someone help me out

 

Common issue is the MAF, followed by ignition coils.

 

Hi there. Did you have any luck fixing this? I'm having the exact same issue currently. Car runs great when it is cold but once warmed up it is very sluggish on takeoff, with some engine judder. I've changed the plus and checked my coils and doesn't seem to have fixed anything.

 

You may have a bad/failing coil pack. If there's a crack in one internally or externally it may be ok cold but as it warms up and expands the crack spreads out causing a short. It's particularly noticeable if yours is an 2001 2.0L like mine because each coil pack fires two plugs and you're essentially losing half the engine.