Chevrolet Aveo LT 1.5 SOHC

[asif980]

Hi guys! I need your valuable input regarding the problem I am facing.
The acceleration of my car in first two gears is very lethargic but once it goes in 3rd gear, it gains speed and is normal. In 2nd gear on 4K rpm it goes on 40km/h. The engine is also scanned and there are no scan codes. The changes I have made till now are as under:
- replaced fuel filter
- replaced fuel pump
- replaced exhaust
- replaced spark plugs and plug leads
-replaced MAP sensor

The starting is ok and engine temperature is also normal.

Can anyone please help me to resolve this issue??

Many thanks,

Asif