Thank you guys both,but may be i did not elaborate properly. Yes the thing is old an 85 model nearly clocking 500thou.To start is not an issue here, i know some hp's aren't good or broken i will replace them anyways, so the car have good block heating and after some cranking it starts normally with some initial misses. The miss i am talking about sounds like there is a chocked filter or air passing thru the system.If when driving on a smooth plain road it misses thru and it became normal again. One day i did travel to another city170km away, on a highway i can cruise normally for about 45 min with a steady 120 km/h and abruptly comes a miss. So it comes and goes all the time and worst thing as the temperature drops further it becomes nastier! Believe me when it is warm the problem goes away totally!! Is there a steel filter somewhere which might be clogged or it contained some water from vapor and gets frozen ? Today temp dropped further below and damn i had to stop 2 times when going to work 3km from my home.