I just got this car and I'm going through the things I know need done. Pulled air filters and they needed replaced desperately. Pulled all plugs and new bkr7e going in tomorrow. (Wouldn't mind someone mentioning recommended gap here). When I pulled I noticed all had pretty good carbon but tips of electrodes clean. Passenger side of engine, all four plugs had noticeable wet fuel on them and the four driver side did not.

After err I get to the bottom of the rough start and extended cold cranking time I plan to do oil change and full timing belt and accessories.

After doing some reading, it seems like the coolant temp sensor is a likely cause of the symptoms I'm seeing. Is there a measuring block I can look at on cold start to monitor this sensor for a false reading when cold? I would just swap out the sensor to check but don't want to mess with loosing coolant if I don't need to.