Possible overheating troubles.. help!

[Globule]

My car has been running nice and cool since I bought it.. usually the needle stays between the A and L in "NORMAL". I always keep a close eye on the gauges 'cuz I don't want anything to happen to my baby Well, two days ago I was driving home from work and noticed the gauge was reading around the O!! Coolant levels are OK and the car is still running awesome. Today I noticed the same thing, although it ran a little cooler, staying around the R.

One goofy possibility - the stock tach needle fell off a few months ago, and it's sitting in the gauge cluster just underneath the temp gauge. It is sitting just right so that the temp gauge needle sometimes sits on the tach needle that is laying there. Is it possible that it like, messed up the calibration of the temp needle at all? I dunno, just random thoughts..

Any ideas?

 

[Globule]

Bump

 

[88gt]

You could just replace the temp. sensor in case it's acting silly or get an aftermarket gauge and not worry about the factory gauge any longer. I've got an autometer temp. gauge in my car and alomost always reads different than my factory gauge. If you want to run both, there is a plug at ther rear of the intake that works as a location for the aftermarket sensor.

Jim

 

[NKau]

Yeah, I'd honestly look into some aftermarket guages; oil pressure and water temp guages are a NECCESSITY in my opinion. Tough to tell what temp you are actually running at without having a reliable guage.
BTW, how the heck have you been running around without a tach needle for a month? That would drive me crazy LOL.

 

[jerry beach]

Forget that stock crap, I run manual oil pres. and water temp. If you cant afford the autometers, get some cheap sunpros from the auto parts store. I have had good luck with them in other cars. Then get a pod to put them where you can see them.

 

[jmuva44]

before you replace every guage you have why not make sure that your guage isnt actually telling the truth? Make sure your fan is turning on, make sure you have enuf water in your coolant mixture, check your ECT sensor (that was my overheating problem), make sure that you dont have any air pockets in your coolant, check your wires to the guage. People are so quick to blame an expensive part on their problems. Check the little things first. After ruling them out, THEN consider replacing guages and radiators and stuff. Good luck!

 

[IndyBlk5.0]

could be a sticking thermostat too... check your fan clutch, make sure its running.

 

[NKau]

before you replace every guage you have why not make sure that your guage isnt actually telling the truth? Make sure your fan is turning on, make sure you have enuf water in your coolant mixture, check your ECT sensor (that was my overheating problem), make sure that you dont have any air pockets in your coolant, check your wires to the guage. People are so quick to blame an expensive part on their problems. Check the little things first. After ruling them out, THEN consider replacing guages and radiators and stuff. Good luck!

There are lots of things it could be, but you must first establish that there is actually a cooling problem, which you cannot do without ACCURATE guages. This is not a simple suggestion; anyone who cares about their engine needs to have good guages to monitor what's going on at least with temperature and oil psi. It's common knowledge that the factory guages are crap, so I won't even get into that.

 

[jmuva44]

The guages are accurate enuf to be able to know whether or not your car is overheating. It may not tell you the actual exact temperature but it will get you pretty darned close. Say what you want but but i'd start by assuming the guage works, which they tend to do believe it or not. Look for faults in the cooling system such as the fan, ECT sensor, air bubbles ect. Buy a new super accruate guage if you must, but the one the car came with works well enuf to judge whether or not your car is overheating. It hasnt failed me yet on any car i've ever had....maybe i've been lucky.

 

[Sgt.5point0]

Have you had this car before at this time of year or at this outside temprature... deviation from norm? Were you running the A/C (if you have it)?A cheap fix would be maybe trying a mix in the radiator with Redline's Water Wetter.

With those type of mods you should have a little bit beefed up cooling system. Alum. 3 core Radiatior, Elec. Fan, Hi-Flow water pump. 180-90 t-stat.

 

[Michael Yount]

I'm with NKau on this one - the stock gauges/sending units are notorious for acting up with little/no warning. If you're not having any other overheating symptoms (low coolant, drivability issues, etc.) then I'd trouble shoot the sending unit first; gauge second.

 

[NKau]

Buy a new super accruate guage if you must, but the one the car came with works well enuf to judge whether or not your car is overheating. It hasnt failed me yet on any car i've ever had....maybe i've been lucky.

True, but there is a big difference between your car running "warm" 200 as opposed to "getting close to harming engine" at 230. But you are probably correct in guessing that there is a problem of some sort.

Globule; need more info. Does the car run warmer at speed, at idle, or no difference?

 

[jmuva44]

Well ya might as well replace the radiator. They are typically pieces of crap. While you are at it, replace the water pump, the stock ones tend to leak. Dont forget the fan motor, they tend to die quickly and often catch on fire. They all suck and are replaced by people who are serious about racing cars so just replace them all. lol....just replace the guage and pray to god that you didnt waste your time and money on something you didnt need. Dont bother actually looking for the problem...lol

 

[NKau]

Well ya might as well replace the radiator. They are typically pieces of crap. While you are at it, replace the water pump, the stock ones tend to leak. Dont forget the fan motor, they tend to die quickly and often catch on fire. They all suck and are replaced by people who are serious about racing cars so just replace them all. lol....just replace the guage and pray to god that you didnt waste your time and money on something you didnt need. Dont bother actually looking for the problem...lol

My point is that you can't even begin to even diagnose WHAT the problem is if you don't even know what the temperature is.

 

[jerry beach]

My point is that you can't even begin to even diagnose WHAT the problem is if you don't even know what the temperature is.

Thats right, and good job keeping calm. My temp guage pegged hot one day and the motor hadnt warmed up yet. I put in a new sender for about $5 and it fixed the prob. Then I promptly ordered new guages. Once you get to 80,000 MI or so its time to put in new guages, that is if you really care whats happening under there. If you choose a 15 yr old elec. guage then you are asking for trouble. My clutch fan started failing and it would creep up in the city at idle while running the AC. So I put in an electric fan and that fixed it, I put in a 3-core brass radiator too, just to be safe. You know what they say, an ounce of prevention is worth a pound of cure. The few items I put in cost me about $300, what does a new engine cost, about 10 times that?

 

[redterror302]

Just a quick question, how do you check for air in your coolant system?

 

[HISSIN50]

i agree with Nick, Michael and Jerry on this one. my stocker would stay under 1/2 mark, while i was actually in the 220-230 range. gauges are something you need irregardless, whether your gauge is at fault right now.

does it run hotter on the highway or in town. hot on highway generally means clogged radiator, and hot in town can be other things, like fan clutch.

5.0 GT, air in the sytem. this is normally addressed upon flushing. just get the air out of the system, especially the heater core area, where air likes to cavitate. the system should bleed itself over time.
you can jack up the drivers side front of the car and take the rad cap off and run the car for awhile. with the rad neck at the highest point on the system, this helps purge air.
good luck to all.

 

[Michael Yount]

Yo hissin' - 'sup? You might want to check your choice of verbs out; I think air might get trapped in the heater core, but I doubt it's doing any cavitating in there.

 

[HISSIN50]

what i was referring to is that there is cavitation in the system. in some industrial applications, cavitation is air being trapped in the system, which may or may not be circulated or caused by the pump. this is not true to the definition, which includes that the impeller created the bubbles, but it is a commonly accepted and term.
you are right, wrong term. air does not cavitate. that's what i get from typing at 2 am.

 

[gt90stang]

To verify my stock temp gauge I used a resistor substitution box, but two resistors can be used 10 ohms (max.) and 70 ohms (min.) if memory serves. Just pull the wire off the top of the sending unit behind the distributor then put one end of the resistor to the wire and ground the other end of the resistor and have someone read the gauge.

Sending units are cheap, but get one from Ford as they have a special spec. so it reads correctly. I once got an aftermarket replacement and it didn't read correctly on the gauge, got one from Ford and it does.

One way to verify the temp is to get a small thermometer and slide the probe part under the protective sleeve near the alternator (this reads very close to the actual outlet water temp). Ford designed the stock temp guage to point near the center at 195*F and at 180*F mine points to the second mark from the bottom 130* mark.

Good Luck, Don