1) Water Temp Gauge Needle continuously...

[9richard9]

stays all the way to the right, outside of the gauge range; even when the engine is off.
No other indications that engine was overheating; radiator was down about a quart of coolant.
1997 Ford Explorer, V6, about 188K miles.
2) At the same time (about 2 weeks ago) this appeared, I noticed my low fuel level light (directly above my water temp gauge) turned & stayed on, even though my fuel gauge continues to work properly.
3) On a very cold morning, about 3 weeks ago, when I started the truck, the starter sounded different upon cranking the engine.
Ever since, each time I go to start the truck, it sounds like the starter strains a few seconds (appears to get longer with each start) before cranking actually occurs and the engine then starts.
I had the battery tested yesterday and it fine / OK, and fully charged.
While I think all these items are unrelated, and that the low fuel level light issue might be due to a bad float in the tank, I'd appreciate your input.
Thanks.
Rich in Central New York, USA

 

[R1dd1cK]

I would go and have your alternator checked out.

 

[97exploderXLT]

Check your coolant temp sensor. On some cars when these go bad it causes the guage to peg out on hot or it could be the guage itself being stuck. The check guage light you referred to isn't just for fuel, it can be triggered by any of the four small guages, its simply telling you hey, look at your guages amd you'll see something is potentially wrong. As for the slow starts, have your alternator checked. If that's not it then chec your starter, sounds like maybe the brushes or the solenoid may be n their way out.

 

[koda2000]

also check to see if the wire going to the temp sender is grounded out. that would cause the gauge to peg on HIGH. If your alternator's voltage regulator was the issue, all your gauges would be pegged, not just the TEMP gauge.

 

[albi1cnobi1]

That light above the fuel gauge isn't just for fuel. It's a "check gauge" light. If any of the gauges go out of "spec" so to speak or out of the normal range that light comes on. Your temp gauge being pegged is probably the culprit.

Edit: Thats what I get for not reading all of the posts. 97exploderXLT hit it on the head.

Check your coolant temp sensor. On some cars when these go bad it causes the guage to peg out on hot or it could be the guage itself being stuck. The check guage light you referred to isn't just for fuel, it can be triggered by any of the four small guages, its simply telling you hey, look at your guages amd you'll see something is potentially wrong.

 

[koda2000]

correct be if i'm wrong, but unlike the oil pressure sending unit/switch, which is more mechanical than electrical, the water temp sender has a mixture of wax and copper particles inside it (like a thermostat). the similarity is that both of these sending units work by varying ohms resistance, on the ground side, to their respective gauges. not saying that a temp sender can't fail, but i believe it's less likely to fail. i'd still check the wire to the sender first. if it has a bare spot and is touching metal, it will make the gauge read full HIGH all the time. when you turn the key OFF the gauge needles stay where ever they were the last when the key was ON.

 

[9richard9]

Thank you everyone for your suggestions; they're very much appreciated.

 

[FIND]

It's most likely a bad temp sender like everyone else suggested, but it is odd to see it pegged even when you shut the vehicle off. Usually with a bad temp sender or a short to ground on the wire, the gauge will reset when you shut the car off... but, this may be an Explorer thing where the gauge just stays up.

Best thing to do is take an ohm meter and test the sending unit.

They aren't hard to change. Just make sure to have the new one in your hand when you pull the old one out, so you can immediately plug the hole with the new one. That will keep you from losing very much coolant so you don't have to worry about draining your coolant before changing it.

 

[97exploderXLT]

correct be if i'm wrong, but unlike the oil pressure sending unit/switch, which is more mechanical than electrical, the water temp sender has a mixture of wax and copper particles inside it (like a thermostat). the similarity is that both of these sending units work by varying ohms resistance, on the ground side, to their respective gauges. not saying that a temp sender can't fail, but i believe it's less likely to fail. i'd still check the wire to the sender first. if it has a bare spot and is touching metal, it will make the gauge read full HIGH all the time. when you turn the key OFF the gauge needles stay where ever they were the last when the key was ON.

The temp sender could have hit a point of infinite resistance and its default is hot for whn it hit that and the guage could've got itself stuck from going up so high. Reason I say this is because in my 300zx if the fuel sender in the tank hits a point of infinite resistancei it causes the guage to read empty at anything under a half a tank causing the guage to show empty and a light oops up on the dash and *****in betty constantly tells me the fuel level is low lol