my 740 when you first start it kinda runs a little rough with a lower idle and smells really rich, the service lights stays on and when i drive it for maybe 2 mins the light goes out and runs alot better but still runs on the rich side of things. things ive done to the car since i just got it

-replaced headgasket
-replaced timing belt
-replaced thermostat
-replaced rear temp sensor
-oil change

just curious if it coulbe be an o2 sensor problem, if it needs a tune up, or replace the other temp sensor, or could it be something else??

 

Does your oil smell like gas?

 

No the oil smells like oil, when i had the head off doing the headgasket i checked the cylinders and pistons and everything looks good, cylinder walls didint show much wear,