Water Temp Gage Erratic???

[dwbailey]

Guys my water temp guge is acting up on my 95 Escort LX hatchback 1.9. It bounces around like there is a short in it somewhere. Bought a water temp sender hoping that is what it is but haven't had a chance to install it yet. Anybody have an idea what might be causing this to happen other than the sending unit failing? Thanks guys.

[mightymoose_22]

Changing the sending unit would be my first suggestion. It is cheap and simple enough to do. Update once you have done that and we can see what further steps need to be taken, if any.

[zzyzzx2]

It's the single wire sensor that it using the carpily mounted inline piece as a ground. Check the mount/ground too.

[AzTumbleweed]

Originally Posted by zzyzzx2

It's the single wire sensor that it using the carpily mounted inline piece as a ground. Check the mount/ground too.

Good point. I never thought about that.

[tripletdaddy]

Ditto on wire grounding and replacing sender. If neither, maybe trapped air?

[zzyzzx2]

FWIW, If for some reason you ever replae the water outlet housing that holds th thermostat, you can replace it with a newer one for newer scorts that has the temperature sending units mounted in the housing.

[denisond3]

I am glad to have that info about the thermostat housing for the later Escorts - as I like to have a mechanical water temp gauge for my cars - in addition to the OEM electrical one.
I have two Escort wagons; a 92 & 94. One of them (the 92) read water temp too high, until I replaced the grounding wires at the negative battery terminal with a soldered connection for all ground wires. The other one reads too low - and I plan to take the instrument cluster off, check the traces and solder joints and connections on the printed circuit to the temp gauge. Im sure the thermostat is okay on the one that reads 'low' on the gauge, due to measuring the temperature of the top radiator hose with an I.R. sensing thermometer by Fluke.

[dwbailey]

Haven't gotten a chance to replace sender yet. Plan to do it over this weekend. I noticed too though that the other sensor that supposedly talks to the computer has one of the wires semi-exposed like somebody tried to pull on it. Not sure if that connector is replaceable or not. Anybody have any idea? The car really cranks long when it is cold like it doesn't want to start and a couple of guys have said that maybe that sensor is telling the computer that the engine is warm when really it is bone cold and that could cause a hard start when its cold. Have replaced the plugs and wires and confirmed that the coil is hot hot. Any ideas guys? Thanks guys and Happy Thanksgiving!

[dwbailey]

P.S. How would you bleed the system of air? I do know that the dealer I got it from put a new water pump on it and maybe didn't bleed it.

[denisond3]

You bleed them of air by just ensuring the radiator is full to the filler neck, then putting the cap on and going for a drive - with the heater on. By the time you get it up to 40 mph it will have moved any air to the top of the radiator. From here the air bubble should either be pushed into the coolant recovery tank, or when you park it and the engine cools, it should draw liquid from the coolant recovery tank into the radiator. Basically you should see coolant right up into the filler neck, anytimg you remove the radiator cap on a cold engine. Removing that cap on a hot engine can let coolant blast out and scald you.
Any of the connectors on the wiring harness are replaceable, though not all of them are easy to find for sale. Somone would have them though, like the dealer if no one else. The connector on the sensor itself would only get replaced via a new sensor.
If it cranks a long time, something is definitely amiss. Temperature sensors are a likely item to 'age'. Try turning the ign key on and off a couple of times without actually starting the car. This will make the fuel pump run, and ensure there is fuel in the fuel rail, in the event you have a fuel pressure regulator that is leaky.

[mightymoose_22]

For the cranking issue I would first suspect spark plugs and wires. Make sure fuel and air filters are clean too.

[EscortDave]

Originally Posted by zzyzzx2

It's the single wire sensor that it using the carpily mounted inline piece as a ground. Check the mount/ground too.

What do you mean by carpily mounted and just where is the ground on this single wire sender.
I also have an erratic temp gauge its been erratic for a long time. It moves with the engine speed at times. Step on the gas it goes to cold..let up and it shows engine temp. I have done everything its still erratic.

[mightymoose_22]

For erratic temp gauge that fluctuates with engine speed, that suggests to me that the thermostat is not working correctly. If you have replaced your thermostat and that did not good, then water flow is likely getting around it through the bypass valve in the housing. Replace the housing and that should solve it.

[dwbailey]

Didn't replace the sender yet because when I looked at it, it looked like the previous owner had replaced it. I pushed the wire back into the connector that plugs into whatever it is that is like an in-line heater hose looking hose with some electrical tape and hope it holds and hoped it fixed the fluxuating guage. NOT! The guage does though at times move around with the acceleration so I'm wondering if maybe I ought to chase the thermostat and housing replacement? Hate to dig into that and the mess that comes with the antifreeze if its a long shot but I guess you gotta do what you gotta do. When I took the radiator cap off the level was low so I filled it up and put on a new cap. Didn't fix it either. Still fluxuates.

[mightymoose_22]

The thermostat housing is about $50-65 at most parts stores, and is usually listed as a water inlet or outlet rather than as a "housing". It is easy to replace, just messy due to the antifreeze.
It might not be your problem... but the symptoms sound right, and it has been a fairly common problem with a car that age.