Q: Car wont start right after driving any distance, if I let it sit, it starts up. on 2003 Nissan Murano

car died, replaced 7 yr old battery & drove home, bad altenator but drove car to work (about .5 mile) for 3 days, P0603 appeared intermitently, installed new altenator and after about 25 miles P0603 appeaered again. we reset code but it comes back aftershort trip. i have cleaned and reseated cables and connectors all the way to the ECM, but code comes back.

Several months ago the brake pedal would do down to the floor occasionally. The mechanic could find nothing wrong. Last Week the pedal started doing down to the floor but the car did stop. The mechanic replaced the master cylinder and all the brake pads. After bleeding the brakes the pedal still goes all the way to the floor.

My murano temp hand goes up while sitting still but when I drive off it goes back to normal. No sign of overheating under the hood.