Can you get any codes read (OBDII reader)? This would be EXTREMELY useful. Two error that could give this fault would be faulty camshaft and crankshaft sensors/wiring.

Could you try swapping the ECU from your Mazda into the Kia? This should give you an idea if the ECU is OK.

They should have the same plug I think... (not sure as we didn't get any earlier than 97 models over this side of the puddle)

2002 Sporty , Ironman 2.5" spring, 2" body, 15 x 7 ROH wheels, K&N, 15 x 10.5 Simex Centipedes, Powerchip 91.

"Never argue with an idiot. They will bring you down to their level then beat you with experience!"