Engine running cold

[scoteric]

I have a 1995 park avenue with 155,000 miles on it. The engine runs cold and will not warm up to 195 degrees F. I have replaced the thermostat two times and it still does not warm up like it did before the new thermostat was installed. The last thermostat was purchased at the dealer and was suppossed to be the correct one for the car. I have also replaced the intake gasket and the water pump. Now that the weather has gotten below 0 degrees F the cars heat gauge only shows 125 degrees F after abot 15 minutes of driving. The car takes a long time to warm up so I am assuming the water is circulating sooner than it should.

[ZiggyPA]

Try setting the temperature on the climate control to its lowest setting and see whether this makes a big difference.

[imidazol97]

Originally Posted by scoteric

I have a 1995 park avenue with 155,000 miles on it. The engine runs cold and will not warm up to 195 degrees F. I have replaced the thermostat two times and it still does not warm up like it did before the new thermostat was installed. The last thermostat was purchased at the dealer and was supposed to be the correct one for the car. I have also replaced the intake gasket and the water pump. Now that the weather has gotten below 0 degrees F the cars heat gauge only shows 125 degrees F after abot 15 minutes of driving. The car takes a long time to warm up so I am assuming the water is circulating sooner than it should.

After driving 15 minutes and the temp showing 125, open the hood and feel the upper radiator hose from the motor to the radiator. It should not be warm because the thermostat should not have opened much at all. It might be warm near the motor for a few inches especially on the bottom from bleed through at thermostat; but the rest should be cold.

If the thermostat is staying closed, it may just be that the heat is being taken out of the coolant by the flow through the heater because of the cold air you're in. There's not enough heat produced by the motor to need the radiator other than the heater which is a small radiator itself. With the blower on high speed, a lot of heat is taken out of the heater and water when the temps are cold. You might try warming the car up for about 5 minutes before driving. But high winds blowing through the engine compartment also take heat from the exterior of the motor (and transmission) when the temps are cold. I just looked up your location and you're as far north in Illinois as one can get, so it's been cold there the last few days.

What does it do if you drive more minutes at highway speeds?

Also try putting the blower speed only on lowest speed at first and see if the air you're getting inside the car is warm.

Have you checked the water level inside the radiator itself when the engine is not hot? Make sure the radiator is full of coolant as well as the reservoir tank is full.

[HotZ28]

In addition, be sure the coolant fans are not running!

[scoteric]

I let the car idle for 20 minutes this morning and it was abot 120 degrees F on the gauge. The heater fan was about mid range set on 90 degrees. I had the hood open to check and did not see the cooling fan running. The car got up to about 135 degrees through town and dropped to 120 degrees on the highway. The radiator is full and the coolent is 50/50 mix. The car is acting like the thermostat is not closing and thus alowing the water to circulate to quickly. I am trying to eliminate any other problems before I buy another thermostat and install. Thank you for the information.

[ZiggyPA]

As long as you have the climate control or heater set on anything above the coldest setting, the car will take a long time to heat up when it is cold.
First let the engine heat up and then the interior.
In really cold areas you can put a piece of cardboard before the radiator, this will cause the engine to heat up much faster. But don't forget to remove it when the weather warms up again.

[RT Jam]

If the fan is not running AND you are not driving. It doesn't matter if the thermostat is stuck open or not. With no air flow through the radiator, it should heat up to normal and eventually past normal.

I'd try that idle test but maybe 5 minutes longer. With the heater OFF.
I'm suspecting the temperature sensor.

Are you sure you are not looking at Celcious numbers?

[imidazol97]

Originally Posted by scoteric

I let the car idle for 20 minutes this morning and it was abot 120 degrees F on the gauge. The heater fan was about mid range set on 90 degrees. I had the hood open to check and did not see the cooling fan running. The car got up to about 135 degrees through town and dropped to 120 degrees on the highway. The radiator is full and the coolent is 50/50 mix. The car is acting like the thermostat is not closing and thus alowing the water to circulate to quickly. I am trying to eliminate any other problems before I buy another thermostat and install. Thank you for the information.

What was the temperature of the upper radiator hose? Was it cold after the first 3-5 inches next to the thermostat? Or was it luke warm along the length indicating the water was flowing through it due to a faulty thermostat?

Let me ask about the thermostat. Did the dealer replace it?
Or did you replace the thermostats yourself?

I remember another case where the owner replaced his thermostat but the gasket was incorrectly placed around the thermostat?
The coolant was going around the gasket!!!

Is it possible your rubber seal isn't in the right place? I believe in the other case the person put the thermostat in then laid the gasket on top and bolted the housing cover back down.

The thermostat sits in the middle of the rubber gasket. There is a groove for the edge of the thermostat to sit inside of the middle of the seal.

http://i86.photobucket.com/albums/k1...7/DSC06213.jpg

This is the gasket <B> inside out </B> to show the groove in which the thermostat goes.

http://i86.photobucket.com/albums/k1...7/DSC06214.jpg

There should not be another paper gasket between the top and bottom housing of the thermostat compartment--just the rubber gasket does all the sealing.

Be sure the rubber gasket is not cracked--they're about $2 at any box parts house.

[scoteric]

I replaced the thermostat myself and the gasket was attached correctly in the groove. I did not feel the upper hose to see if it was warm or not. I bought the last thermostat at the dealer with the gasket already in place. The car used to heat over 200 degrees before the thermostat was replaced. I replaced the thermostat as preventive maintenance and not because of failure. I did not test the thermostat in hot water before installation. I will check the hose in the morning to see if it stays cold or warms up while idling. Thanks for all of the input.

[imidazol97]

Originally Posted by scoteric

I replaced the thermostat myself and the gasket was attached correctly in the groove. I did not feel the upper hose to see if it was warm or not. I bought the last thermostat at the dealer with the gasket already in place. The car used to heat over 200 degrees before the thermostat was replaced. I replaced the thermostat as preventive maintenance and not because of failure. I did not test the thermostat in hot water before installation. I will check the hose in the morning to see if it stays cold or warms up while idling. Thanks for all of the input.

Do you have the previous thermostat so you can put it back in?

If the temperature changed with the new thermostat, maybe it's defective.

[ZiggyPA]

Originally Posted by imidazol97

There should not be another paper gasket between the top and bottom housing of the thermostat compartment--just the rubber gasket does all the sealing.

Be sure the rubber gasket is not cracked--they're about $2 at any box parts house.

The thermostat housing of my 1991 base model is leaking a bit.
On Rockauto I see they offer no less than 7 thermostat seals and housing gaskets for the 1991 base of 5 different types.
So which one do I need, I am surprised to read the paper gasket isn't necessary (even though it seems to match the housing)?

[rawn27]

I have a 95 PA with 177k and I'm having the exact problem that scoteric described in his thread. It started doing that at the end of last winter. When I start it on a cold morning it takes alot longer than it used to to warm up especially if i have the heat on inside the car. It will warm up twice as fast if I leave the heat off. I've also noticed that no matter how much i warm it up if it's a real cold morning and i get up to highway speeds or even like 80kmh the temp drops back down to bout 100 to 110 and stays there until i slow right down or stopped and iddling. My rad is full with coolant and my coolant resevoir is filled right to the line. I checked my coolant about a month ago just to make sure it wasn't burnt out and needed to be changed it was 100% fine. Like some of you described in your posts when i have the heater fan on lowest setting the heat coming out is much hotter and the engine temp tends to be warmer than if I had the fan setting on max. It's gonna be pretty cold here tonite so later when I go out I'm gonna try not turning the heat on inside the car at all just to see if it will run hotter at highway speeds..

[ZiggyPA]

Originally Posted by rawn27

It will warm up twice as fast if I leave the heat off.

At least this would be normal. The heater core in the car is warmed by the coolant. If you put the heater on the engine pretty much has to warm twice as much coolant, and then it gets cooled by the heater core, too.
For the same reason you have a thermostat which only opens access to the radiator at a certain temperature.
Read Imidazol's post and check, you probably have to replace your thermostat as it doesn't seem to close properly.

[imidazol97]

Your thermostat is probably not closing completely. Even a slight bit of opening can allow coolant through and makes it impossible for the engine to stay at temperature.


Your thermostat should be replaced and make sure thermostat goes into the rubber seal correctly.

[rawn27]

I'm in toronto. It's not as cold as I thought it was gonna be but still chilly right now at -3c/-8c windchill ( not sure if the windchill plays a factor here ) what's involved in replacing a thermostat and how much should it cost?
Thx for the info..