water temp gauge

[Turbocpe]

Hold on here. BlazerLT, you need to take the same advise yourself. You jumped to conclusions and said

Thermostat needs to be changed.

It is stuck open.

Having the guy replace something that isn't needing not only costs him money, but time.

Originally Posted by BlazerLT

...but let's not jump to conclusions and state that the stat is fine.

[blazee]

Originally Posted by BlazerLT

Thermostat needs to be changed.

It is stuck open.

When you replied you didn't state that any other component maybe at fault. I was clarifying that there were more likely causes to the problem.

Hell... it may not be either one.

[blazee]

Originally Posted by Turbocpe

It would be good if you could have someone hook up a scantool to your Blazer so that they can read what temperature the engine is reporting to the computer itself.

Sure would save replacing parts that aren't needed.

Judging by the info here, I would suspect the sending unit or gauge, especially if you have "awesome heat" still.

That sounds like a good idea.

[BlazerLT]

Originally Posted by Turbocpe

It would be good if you could have someone hook up a scantool to your Blazer so that they can read what temperature the engine is reporting to the computer itself.

Sure would save replacing parts that aren't needed.

Judging by the info here, I would suspect the sending unit or gauge, especially if you have "awesome heat" still.

Very true, that would be an excellent reference and would point out the problem immediately.

Great idea Turbo!

[mtrotter70]

I would lean toward the thermostat being stuck open.
I had the exact same symptoms - temp would not go above 110 and
heater worked but not as quite as hot as usual.
Changed the thermostat and problem fixed.

[BlazerLT]

Originally Posted by mtrotter70

I would lean toward the thermostat being stuck open.
I had the exact same symptoms - temp would not go above 110 and
heater worked but not as quite as hot as usual.
Changed the thermostat and problem fixed.

Yea, me too, when it happened to me, the temp would only get up to around 100 in my truck.

New stat and voila! everything was fine.

[Turbocpe]

Well the poster is in NY (I'd imagine a little cold up there) and he says he has "awesome heat". A stuck t-stat sounds less likely based on the poster's description, which only he knows for sure since this is his vehicle and he is working on it.

I've had stuck open t-stats before so I do have some direct experience, but never had "awesome heat" with any of those stuck t-stats. Especially not within 10 minutes like the poster says.

Just my take on it. Nothing more.

Still would be best to get a scantool on it and view the live data and see what temperature the sensor is reporting to the computer itself.

[BlazerLT]

How exactly do you judge awesome heat?

100 is still very warm.

[Turbocpe]

Well, I don't belive 100F is "awesome" heat, nor very warm. But that is an opinion. Plus, only 10 minutes to warm up is not a good sign of a stuck t-stat. That is a short period of time for the engine warm up, especially when you consider that the anti-freeze will be flowing through the engine and radiator right away (stuck t-stat).

It would be nice if people weren't resorted to replacing things at random to fix the problem. I don't like when people are told to replace things, without further testing and diagnostics. That is simply guess work. Sure it may be working, but I call that luck

I'd rather not argue, which is why I've deleted a few of my past posts, or held back from posting, whenever I've seen people on here flat out told to replace X part, without further diagnostics or asking questions to further isolate the issue. That is the wrong way to work on vehicles. It costs the person time and money, and that is something I've seen on this forum in my time here (sorry to say). It is also something that is a frequent problem with people working on vehicles.

I may have a newbie title, but I'm not new to working on my own vehicles, nor am I new to any of these message boards.

The best way is to verify that the temperature gauge is reporting the proper temperature as I said in my other reply. Until that is done, nothing here is going to help further, other than speculations.

Anyway, again, I want to make it clear that I'm not wanting to argue, not with any one person. I'm obviously trying to help with the small knowledge and supply of information I have.

Thanks.

[scholzee]

Its easier and cheaper to replace a T Stat then to find, purchase, or pay someone to hook up a scan tool and read the sending unit, especially if the T Stat has never been replaced or unknown when it was last replaced. If you do not want to spend any money and test the sending unit, start a pot of boiling water, disconnect the wire, unscrew sending unit, hook wire back up, put the threaded end in boiling water, turn key on and watch gauge, it should be close to 190- 212 definitely will go higher than 110 if it is working properly.

[Turbocpe]

Doesn't AutoZone read codes for free? Never used them as I have my own scanner, but do they use the cheap scanner that only reads the trouble code digits? Or do they have the Actron ScanTool (they sell this item, or atleast used to) that displays a few lines of data (live data and trouble codes)? If the later, you should have no problem.

I don't know why you'd have to pay someone to show you one value from the computer. There may be someone he knows that has access to a scanner and would do it for free.

It could be the t-stat and it may not be. Since it isn't a high dollar item and is fairly easy to replace for most people, it isn't as big of a deal in this case as other cases. However, I'm just saying, it just isn't the proper way to work on vehicles and WILL cost the owner more money and time than needed by replacing items without further diagnostics. I don't think that most people care to burn money and time. Maybe I'm wrong.

[blazee]

I, too, made my judgement based on him saying he had "awesome heat" leading me to believe that the thermostat isn't the culprit. 100c would be "awesome heat" but not 100f, it is less than 2 degrees more than your body temperature, 100f air blowing on you would have more of a cooling effect.
I used to have an old 70's model Wagoneer, when the thermostat went out I took it out and it would take at least twenty minutes before it was warm enough for me to feel the heat and I live in Florida.

I believe the engine is getting up to operating temperature but the gauge isn't showing it. This could be the sending unit, gauge, or even a loose wire.

All these parts can be tested if he can't find a place to scan it for free:

To test the thermostat take it out, look at it, (Is it open?) put it in water on the stove, it should open around 195 degrees

To test the wires and gauge, ground the wire to the sending unit with the key on, the gauge should read full scale.

To test the sending unit, according to Haynes:
1. Remove the sending unit from the engine and clip ohmmeter leads to the sending unit body and the terminal. Place the sending unit in a pan of water on the stove, with a cooking thermometer in the water. On a cold (50-80 degrees F) sender, the resistence should be 5,700 to 2,200 ohms. When it has warmed up to operating temperature (170 to 200 degrees F) the resistence should drop to 200-300 ohms.

[MJTrippy]

ok sorry about saying awesome heat, i beleave its the t stat, the heater blows not that hott anymore after all this, i mean it blows heat but not as good as it used to, and after driving for about 30 min the needle moves off a 100 to 110 maybe(bearly moves), and it looks very hard to get the t stat off and check it, any tricks to get it off without a hasle????

thank you

[BlazerLT]

Originally Posted by MJTrippy

ok sorry about saying awesome heat, i beleave its the t stat, the heater blows not that hott anymore after all this, i mean it blows heat but not as good as it used to, and after driving for about 30 min the needle moves off a 100 to 110 maybe(bearly moves), and it looks very hard to get the t stat off and check it, any tricks to get it off without a hasle????

thank you

Do you have any automotive or repair experience at all?

[MJTrippy]

yes some i;m pretty good with cars