Engine Mechanical problem
2001 Hyundai Amica 4 cyl Front Wheel Drive Manual 89000 miles

Hello,

Last year local garage changes the spark plugs for my car, timing belt, oil & air filter and it was fine but after 8 months - (in winter) when i start the engine first time in the morning check engine light on and engine start missing but doesnt turnoff.

if i put car in first gear for drive it move on after alot of acceleration and same happenes when i am on 50 or 60 if i press the acceleration full the engine starts slowing down from 60 to 50 but not to 70mph.

I am confused as timing belt engine oil and everthing is fine + spark plugs were changed last year as well.

and it happenes randomly.. some times it become fine and no problem at all.

confused....!

thanks
regards