recently when i had been driving my temp. guage would go up past the middle a little bit then come right back down, no big deal. now when ever i idle at a light or drive thru my temp. guage spikes and it went into the red one day. so naturally i suspected something was wrong with my cooling system and ordered a new thermostat, thermostat housing, and im gonna empty and refill the whole system, but last night i went to a scuba class and had my car sitting for easily two hours in cool weather. when i got back later the guage turns on just a little below hte middle line, now is it me or does that seem off that the car would stay that hot for that long? so now im wondering if my guage is messed up. any input would be awesome, thanks.
<img src='http://img268.echo.cx/img268/1430/zkwsig23iq.jpg' border='0' alt='user posted image' />
1996 328is Black
Suspension: MB Motoring 18x8, Kuhmo Supra 225/35/18ZR
Audio:Eclipse CD3414 HU
Lighting: ZKW W/ DDE PLUS