Temp Gauge 94 escort

[mrbreezeet1]

Question
Where does the temp gauge run on your escort?
I have a 94 escort with the 1.9 L motor.
Thought it should run around the middle, but mine only rund around the "N" in "NORMAL"
Replaced the T-Stat with a 190 from advance, but still the same.
Thanks Tony

[mightymoose_22]

It should typically rest somewhere between the O and the R.
When the sensor goes bad it will normally indicate an undercooling situation as you describe. The sensor is in the heater core output hose that leads to the thermostat housing. There are two sensors there. The one you will want to check is the rear one.
Also, I believe the thermostat is supposed to be 180, but a 190 thermostat would not cause undercooling symptoms.

Another possibility, if it is not the sensor, is that the bypass valve in the thermostat housing has gone bad. If the valve is broken or stuck open then coolant gets around the thermostat preventing the engine from reaching normal temperature.

The sensor is cheap. Replace it if you have never done so before. If your problem isn't fixed, focus on the housing. The housing is available at the major part stores but is listed as a "water outlet". I searched for it forever before I found out how it was listed. I think it runs around $65.

[mrbreezeet1]

Ok Thank You
Ok So is the sensor a dealer Item? Or can I get it at the parts store?
So it's right in the hose?
Don't think I ever noticed it. When you say the rear one, do you mean toward the fire wall?
See I have some heat, but not like it should be.
Someone suggusted a blocked heater core,but I thought 1st maybe the engine was not coming up to normal tempature.
Wonder if I should focus on the housing 1st?
Or if it's possible to free up the valve in the housing.
Not real sure how it works.
Maybe if its cheap enough(sensor)I'll replace it 1st,but since I'm not getting the proper heat, I thought I'd look torward the engine temp 1st.
Tony

[mightymoose_22]

Ok... you added information. If you are lacking heat then you probably have something other than a bad sensor.
You either have a bad housing as previously mentioned, or a blocked core as you stated.
To test the housing you should be able to feel for flow through the upper radiator hose. There shouldn't be much until the engine reaches temp and the thermostat opens. If it feels constant, especially when cold, then you have a bypass problem.
The core is simple enough to check by disconnecting the input/output lines and putting a regular garden hose up to the ports (with low pressure). Water should flow through freely. If not, there is blockage. You may be able to backflush it and clean it out, but be careful not to use too much pressure.

[tripletdaddy]

If the Escort has some unique anatomy that I am not familiar with in its cooling system, then some of what I will say that is typical of most other engines won't apply. If the thermostat is stuck open when starting a cold engine, the tstat (the valve I assume MM22 states) is supposed to stay closed to bring the engine and heater core up to operating temp as quickly as possible by keeping the coolant trapped in the engine, the bypass hose loop and the heater core loop. Not to be picky, but the water pump pushes the coolant thru the engine exiting at the bypass hose, thermostat and heater hose, not the reverse. If the tstat is open when the coolant is hot enough, then the radiator loop is included. All loops return to the water pump. As MM22 stated, with the tstat open when it shouldn't be, it takes much longer for the engine to reach operating temp and possibly not at all in very cold conditions. I'm not familiar with any additional valves involved in the water outlet/thermostat housing, but maybe that's something new for me. It's not beneath me to be wrong.

I was able to confirm that the OEM temp for the tstat is 190 - 192 deg F.

If you have an ohmmeter, you can test your coolant temp sending unit. Cold is 74 ohms to hot 10 ohms. If you take the wire to it and ground it, your gauge should go to the hotest. Without a meter, you can check your unit if it reads too hot when the engine is cold right at first startup by disconnecting the temp sending unit wire. If the gauge drops to or near bottom, the unit is bad. If it remains high, the wire to the gauge and unit, the unit, the gauge in the dash, or a hot engine light(if you have one) may be shorted to ground or they are faulty.

[mrbreezeet1]

Ok Thanks Guys.
Yes I did with hold the information about the heat,because first I wanted to see where other escorts temp gauges are running.
I am/was thinking first off that the motor is not running at quite normal temp.
Still might have some heater core blockage, but wanted to focus on the engine temp. first.
I will check the sensor with an ohmmeter, and go from there.
May be a week or two before I work on it,but I will follow up on what I come up with.

Tony

[mightymoose_22]

This model Escort has a valve in the thermostat housing that allows coolant to bypass the thermostat itself. There are some lengthy posts regarding this valve in the archives of this forum.

Mrbreeze... focusing on the engine temp problem while ignoring a possible heater core blockage is a bad approach. Because of the placement of the coolant sensor, heater core blockage could be the very cause of your problem. If coolant does not flow through the core properly then the sensor does not pick up the temperature.

A simple way to check the core without unhooking anything is to turn the heater on high and feel the heater hoses going in and out of the core. If it is hot going in and cool coming out, you have found blockage. However, you may not have a complete blockage, so removing the hoses and visually checking the flow is better if you can't quite tell by touch.

Has this car had any prior overheating problems? Why were you replacing the thermostat in the first place? Also... have you made sure that after replacing the thermostat you have properly refilled the coolant?

[mightymoose_22]

A couple links to archives for reference.

https://www.automotiveforums.com/vbulletin/showthread.php?t=486552
https://www.automotiveforums.com/vbulletin/showthread.php?t=212393

[mrbreezeet1]

OK makes sence about the placement of the sensor.
I will read the posts about the bypass valve,
and run some water through the heater core and see what I get.
NO, never overheated since I have had it at least(about 5 years)
I replaced the thermostat trying to get the motor to run a little warmer.
Yes I am sure the system is properly filled, and no air pocket.
I did feel both hoses today, and they seem "about" the same.Kind of hard to tell, but nothing drastic in the difference between the 2.
Will be sure to follow up when I get to it.
Tony

[mrbreezeet1]

http://www.automotiveforums.com/vbul...d.php?t=486552
http://www.automotiveforums.com/vbul...d.php?t=212393

Well after reaading these posts, not sure what to think.
Seems they did not see much of an improvement.
However seems this guy did.............
http://www.theyeagergroup.com/escort_wagon.htm
"Success! The "vapor by-pass" in the thermostat housing had failed (as indicated by a rattle in the thermostat housing detected while the housing was removed to change out the thermostat) and was letting a lot of coolant past the thermostat. Cold weather fuel mileage jumped about 4 to 6 MPG (depending on whether it is highway or combined fuel mileage) after replacing the housing with one from a '91 Escort."

The first tank full after housing replacement was just over 34 MPG with the outdoor temperature in the 30s and 40s, the cool air intake intact, and no baffles in front of the radiator. Once warmed up the stock temperature gauge was rock solid in the middle of "normal". Seems that ECU is very sensitive to not only the coolant temperature but any coolant temperature fluctuations as well.

seems one of the 1st 2 links above they said the new housing had the rattle in it too.
Well Like I said, I'll flush the heater core 1st and go from there,
Would be nice as a side note if gas mileage improved too.
Tony

[mightymoose_22]

I once had an under cooling situation with my own vehicle and fixed it by replacing the thermostat housing as well... and I think I only did that because of the info in those posts. I doubt I would have thought of that on my own.

[mrbreezeet1]

Originally Posted by mightymoose_22

I once had an under cooling situation with my own vehicle and fixed it by replacing the thermostat housing as well... and I think I only did that because of the info in those posts. I doubt I would have thought of that on my own.

So you have an escort too then?
What year is It? I assume the motor is a 1.9L also?
No this is the 1st I have heard of this also.
It has been intrestring.
Where is the best place to get the housing,
Guess I'll call Advance and Auto Zone.
Thanks for all your help.
LIke I said it might be a week or 2 before I can do anything,
as I have to do the exhaust flex pipe next.
Last week it was the rear alternator bearing,
This week the sway bar links and right outer tie rod end,
I would like to do the water bump and timing belt too.
Tony

[mightymoose_22]

My Escort is same as yours.

[EscortDave]

I also have a 94 escort with a temp gauge problem. I will post my question here instead of starting a new thread.
The temp gauge seems to show engine temp but when you step on the gas the gauge drops down to cold, all the way to the bottom left of the gauge. Let up off the gas it shows the temp. It just started doing this I haven't even had the hood up and bam the gauge flakes out on me.

[mightymoose_22]

Dave, I would suggest that your problem is more related to the gauge itself. Maybe a bad gauge, maybe a bad ground or other wiring issue.