Hi,
Here are the parts that I have replaced.
-fuel filter
-air filter
-OVP
-Cold start valve
-Coolant temperature Switch
-engine temp sensor(at Air Filter Housing)
-Fuel Pump check valves
-spark plugs (bosh non resistor)
- added techron twice.also ( I only use Mobil gas )
-Sea foam treatment
-checked injector and vacuum hoses with starting fluid for leaks.

Thanks everyone for helping I really appreciate.
AJ