Alfa GT JTS idle missfire and slow temp issue
I have a 2005 GT, it's a 2.0 jts and firstly I must say, it's amazing. Two small but niggling faults are, at idle regardless of temp out side, it will occasionally miss fire, this will occur every 5-10 seconds. It never does it on acceleration and pull ok through the gears all be it no wear as quick as my previous 2.0 ts in my 145. Is this common and is it an easy fix does anyone know.
Issue number two is, the engine never seems to get warm, it takes at least 10-15 mins driving to get it to 70c and vary rarely gets to 90c. I guess it maybe a thermostat issue, I only average 21/22 mpg as well, could this have something to do with the cold engine over fueling.
The car has done 100k but has good service history and I have just had all belts done.
Any help would be so appreciated.
Thanks in advanced