after changing the water pump the acceleration of the car being very heavy its likely very hard to accelerate with it
Che k the belt timing; it's probably off a tooth.
You better get that looked at from whom ever put that pump back in. If i'm not mistaken the 2.0L engine is an interference motor, therefor, if your timing belt is a tooth off, then your pistons can hit the valves and grenade your engine.
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