03 tl type-s, driving it is fine...after 20 mins of being warmed up, if i come to a stop, itll start almost going up in the red. also, after it's driven and gets hot, it doesnt like to start back up (occasionally). It just wont turn over. Both fans are on, coolant levels are good.. thermostat is good, what are some things that could be problems? i just replaced the ignition coils and spark plugs aswell. 146k miles, and doing the timing belt soon. could it possibly be the water pump ?

 

i had this exact same issue after i replaced my throttle body, but realised it was because i had no coolant! :p

in your case, it may very well be circulation-related (as was mine, but filling 'er up did the trick).

it would overheat in idle, and you have to let it cool down before starting again. and when you do start it, it's a very "hard" low-end start (sort of like a semi truck) before hitting normal RPM.

have you tried the "test" in 10-12 of the service manual?

it states:

1. remove the timing belt (see page 6-18) <--- YEOUCH!
2. turn the water pump pulley counterclockwise. check that it turns freely.
3. check for signs of seal leakage. a little bit of weeping from the bleed hole is normal.

 

My '01 just had this issue. Would over heat at long stop light or drive thru's. Once you took back off the temps would come back down. Replaced serpentine belt two days ago and fixed the issue.