Focus Duratec Thermostat Replacement

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SwampSurvivor

SwampSurvivor

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So posted some questions on both Reddit and Focusfanatics and not getting any response. Maybe someone on BITOG can provide an answer.

This car has never been great at making heat. Often won't come up to temperature in the winter. The thermostat has been "replaced" by a dealer - but I never received any paperwork and I believe it was not actually done.

From the factory, it had a 180F thermostat. Ford only makes a 190F after many complaints of P0128 and people not having satisfactory heat. It's a chronic problem, apparently.

I want to replace my thermostat with the 190F unit.

Does anyone know how to do this? I watched two videos on youtube. Each says their way is the only way to do it. One way just involves disconnecting the AC pressure switch and then removing the thermostat. The other involves removing the PS pump, engine mount, belt ... way more than I want to. On focusfanatics, the guide says to remove ps pump, engine mount, intake manifold, belt ...

So , any thoughts on that?

I believe the 190 T-Stat will be a huge improvement.

Also ... at which temp is the fan going to kick on? I don't want the fan to be running 24/7
 
After seeing the thermostat under the intake manifold, I had Ford replace mine in the 07 Focus.
 
I am likely going to bring it to an indy mechanic to have it changed. Just trying to get an idea on what would have to happen.

The other thing is, I can't tell if I have the thermostat/housing with a sensor or without. I think the PS pump may have to come off to tell.
 
Should be no biggie to get the pump off; are you good with removing belts? If so, unbolt the pump and lay it out of the way to get a look.

I would definitely be concerned about the fans running all the time with a higher temp thermostat.

Have you looked elsewhere? Does the gauge come up on the dash to operating temperature? You might want to try an infared heat gun on the radiator hose coming out of the thermostat, or better yet, hook it up to a scanner, and see what the actual coolant temp is after it's run for a while. Ultimately, the problem could be a blend door or other HVAC issue. Unless the thermostat is actually sticking open, I've never found fiddling with thermostat temperatures to be a good option; anything you gain in the winter will cause issues in the summer or vice versa.
 
I doubt you would even notice much out a a 10 degree difference with respect to heat, unless the existing one is stuck open, or something. I would see how hot the radiator and heater hoses are getting with one of those thermometers that uses a laser pointer type of thing first. And if the car is warming up just fine, check the blend door and/or HVAC controls. For all I know you have a clogged HVAC filter, or something.
 
^^^ +1 I think youre barking up the wrong tree. 10 degrees wont fix the real problem. I would look at the routing of the heater core or air flow problem in the ducts. For some reason it is not getting enough flow.

if 180 degree collant is getting to the heater core and air is moving across it and blowing out the vents it will be plenty hot.
 
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I also think the capacity of these systems indicates the poor heating abilities. The system only holds roughly 5 litres of fluid from empty.

OTOH, my MIL used to rave about the abundant heat her 2005 Focus used to put out even after a short drive. She lived on the prairies so she knows a good heater when she sees one!
 
My Mazda 3 has the exact same engine as your focus, however my car only has the belt tentioner in place where the PS pump is on the Focus. However, once the tensioner, and it should be similar with the pump, is removed, there is enough access to disconnect the hose and remove the thermostat. It's a whole housing type.
From my experience with other cars, the PS pump should be able to be unbolted without draining the PS fluid and simply put aside.
 
Originally Posted By: zzyzzx
I doubt you would even notice much out a a 10 degree difference with respect to heat, unless the existing one is stuck open, or something. I would see how hot the radiator and heater hoses are getting with one of those thermometers that uses a laser pointer type of thing first. And if the car is warming up just fine, check the blend door and/or HVAC controls. For all I know you have a clogged HVAC filter, or something.


I believe the current thermostat is stuck partially open, or won't close completely. Blend door actuator does work. Once it gets up to temperature, it can get warm or cold as needed. But if I go down a long hill or even sit still in a parking lot with the heat on, the temperature drops.

Originally Posted By: Drew99GT
Should be no biggie to get the pump off; are you good with removing belts? If so, unbolt the pump and lay it out of the way to get a look.

I would definitely be concerned about the fans running all the time with a higher temp thermostat.

Have you looked elsewhere? Does the gauge come up on the dash to operating temperature? You might want to try an infared heat gun on the radiator hose coming out of the thermostat, or better yet, hook it up to a scanner, and see what the actual coolant temp is after it's run for a while. Ultimately, the problem could be a blend door or other HVAC issue. Unless the thermostat is actually sticking open, I've never found fiddling with thermostat temperatures to be a good option; anything you gain in the winter will cause issues in the summer or vice versa.


It is a Ford, so the gauge on the dash is, for the most part, fake. Watching the temperature with an OBD scanner, it will come up to temperature slowly. The most it runs at is 180. And running the heat or anything in the winter, without a load, the temperature will drop down to 150,140, 130.

And forget about "warming it up". If I cold start it and let it run all day, it will never get above ambient.
 
It's a PITA to replace the thermostat on the Focus. Usually cussing and a 1/4 inch air ratchet is how I replace them. The P.S. does not have to be removed but it would be nice if it wasn't there but it creates even more work. The work required to remove the RF tire, belt and p.s. pump outweighs the benefit (and I don't have time for that at work).

Burping them is difficult as well because the hot coolant bypasses the thermostat and runs through the 5/8ths bypass opening right next to the thermostat.
 
I'm leaning more towards sending this one to my mechanic once I figure out which thermostat I need. Sensor or no sensor.

I guess I am lucky to live on a hill. A steep hill. I can drive it up on the lawn to get even more angle.

The fact that a few have said their heater works great and quick means something is wrong with mine, somewhere.

Plus, it wouldn't hurt to get new coolant in it. The car is technically 5 years old (built late 2010) and it is nearing 60K miles.
 
Awesome! Thanks for finding that! I'm going to order it tonight, pick up some G-05 coolant.

Just gotta fix the Jeep and then I will schedule something for the Focus.

I don't think this is one I will be doing myself. I really don't like playing with belts.
 
Ya it is a weird lookup. I put your VIN in our regular parts catalog and it gave both options. However when I ran it against the Build of Materials on Ford's end, it came back with the one without a sensor.

The sensor is pretty easy to see, the hex part is rather shiny.
 
Originally Posted By: beast3300
I haven't had a Focus/3 with the built in sensor yet. Maybe it wasn't too popular.


My guess is something like a Ranger or an Escape that used the engine has it? Something in the family uses it.
 
Originally Posted By: Miller88
Originally Posted By: beast3300
I haven't had a Focus/3 with the built in sensor yet. Maybe it wasn't too popular.


My guess is something like a Ranger or an Escape that used the engine has it? Something in the family uses it.


That could be, at my previous employer the shop truck was a 99 Ranger. It had the 2.5L, 8 spark plug engine in it. It also had a thermostat housing with 2 sensors in it. I don't remember if the house was with thermostat or not, but it was cracked and needed replaced.

edit: Not the same family as the 2.0/2.3. Maybe a truck thing with the sensors though.
 
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Originally Posted By: Miller88
The thermostat has been "replaced" by a dealer - but I never received any paperwork and I believe it was not actually done.


Are you sure the replacement thermostat wasn't one of those poor quality Motorad "fail open" types that we keep telling people not to use?
 
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