When its like over 50 degrees outside my 94 ex gets warm pretty quick and stays good and warm. But when its colder outside like recently when its been 10 degrees out, the car has trouble warming at all. If I do let it sit somewhere for like 20 minutes it will warm up, but then if I drive on the highway it cools back down to under the blue mark. In fact if it warms up and I just drive like 3 blocks at 40 mph it gets cold again. Is it just the thermostat? Any have this happen?

 

It's impossible for you to drive and the engine get colder. More than likely your thermostat

 

is a new tstat like 10 bucks? Pretty easy to change on the f22?

 

Not sure, never had a problem with mine but here's a bump so someone else can help

 

The thermostat and it's gasket should be around $10 at your local parts store. You'll have to drain about a quart may be two of your coolant. If you plan to re-use it be sure to use a clean bucket. Then remove the air intake piping between the air box and the throttle body. This makes it easier to get to the thermostat housing. Remove the large diameter hose from the housing and the two retaining bolts in the housing. Tap on the housing with a rubber mallet to brake the seal and pull out your old thermostat. Be sure to note the orientation of the thermostat. As I recall the spring faces the engine. The orientation of the pin is important as well. 11 or 12 o'clock is how I remember it.

Put the new gasket around the replacement thermostat and install the thermostat. Torque the housing retaining bolts, attach the lower radiator hose and and crack open the bleeder screw found on top of the thermostat housing. Refill the radiator, you'll need to close the bleeder screw when the bubbles stop and are replaced by a steady stream of coolant. Install the intake plenum start your car and check for leaks and heat.

 

I have the same problem too. My engine also revs up and down when the engine gets really cold. I hope it's the thermostat!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TxTuner &raquo;</TD></TR><TR><TD CLASS="quote">It's impossible for you to drive and the engine get colder. More than likely your thermostat</TD></TR></TABLE>

True but it is possible for the car to idle and get colder. ******* **** happens all the time at stop lights on the way to school in this subzero weather.