My car takes forever to heat up and when it does the needle on the gage hardly ever reaches the "N".Even after prolonged idling with the e-fan unplugged.I let it warm up to the "N" one day and checked the coolant temp. with a thermometer and it read 160* so I dont think its the temp gage.I've replaced the T-stat twice and both times with Mr.Gasket stats.When the weather is warm it has no problem heating up............???