I own a vw jetta mk6 1.4tsi. in the morning when i start the car, it will misfire or rough idle for 5 to 10 seconds before it idles normal. what cause it to misfire and how can I rectify this problem?
I have a 2017 Jetta 1.4tsi 5 spd man. On the coldest days in the northeast have never had misfire or rough idle on start up. Like the other person stated depending on mileage and how the car is driven there could be a number of possibilities. Check plugs, standard thing to do, if you have a heavy foot and over 30,000 miles on the car you can have buildup on your intake valves because of direct injection. if this is the case eventually the condition will get worse. So check plugs to see if they need cleaning or replacement, after that if condition worsens you can try to clean intake valves with one of the do it yourself spray in cleaners like Seafoam or CRC. You need some mechanical ability and a second person makes it easier to hold RPM with pedal, or take it to a professional and they normally clean with pressure blown walnut shell material. This last method will clean valves guaranteed but will cost in range of around $1,000 more or less. Also you can check if there are any codes, live or pending thru the obd port, sometimes there are codes without check engine light. If you know any one with a good code reader that would be great, if not you can purchase a OBDeleven reader which is specifically for VW and Audi. Buy the PRO version for the difference in cost to the standard version it is much better. You can go to their site for specifics and decide what you want to do.