2004 Tahoe operating temp issue.

[rockola1971]

It sits here when driving.

Engine temps while driving look completely normal. What is the temp at idle?

 

[Fless]

Engine temps while driving look completely normal. What is the temp at idle?

Idle values from post #2:

 

[Scottydoggs]

you might want to grab and hold the heater hoses, engine up to temp. see if they are hot. both should be warm to hot. if one is hot and the other cold the heater core might be air bound, or clogged up.

ive got warm air in my hoe as soon as the needle lifts off the lowest temp.

 

[nonickatall]

I do not think that you have a technical problem. I know a lot of cars and they all need different time to get hot. The big V8 engines need longer than modern diesel engines, which have mostly additional heaters to reach fast the operation temperature because of emmision purposes.

See it like this. Engine heat is a waste of propulsing Energie. So ist takes a while until there ist enough energy wasted, to reach operating temperature.

Mine as well needs 5 Kilometers or more to reach temperature.

If you want that you car reach temperature faster, for example if you life in a cold area, use an auxiliary heating system.

 

[Doubeleive]

the temp dropping at idle is not at all normal in my book, once up to operating temp it should stay there under normal conditions regardless if it is 10deg or 100deg outside

 

[rockola1971]

This reeks of a bad thermostat OR air pocket trapped in cooling system. The lower hose should not be cool to the touch.

 

[93M6Formula]

So the other day I put a clamp on the hose to the coolant tank so that it barely flowed. It warmed up much faster for sure but then ran a tad warm, but still around 203° according to my scanner. Opened it back up and back to long warm up. And yes the lower hose is cool. Heater hoses are fine, it makes heat. Thinking it's probably going to be just another junk stat, idk why it's so hard to get a good one.

 

[rockola1971]

So the other day I put a clamp on the hose to the coolant tank so that it barely flowed. It warmed up much faster for sure but then ran a tad warm, but still around 203° according to my scanner. Opened it back up and back to long warm up. And yes the lower hose is cool. Heater hoses are fine, it makes heat. Thinking it's probably going to be just another junk stat, idk why it's so hard to get a good one.

203 is not "a tad warm". Its actually closer to normal.

Start your engine up cold and watch and the temp gauge to see what the highest it achieves until you all of sudden see it start to drop (which means your thermostat just opened up). WOuldnt hurt to ignor your temp gauge and hook up a scanner and get temp data from there while watching temp gauge to see the drop. Your scanner data temp may not respond fast enough for you to get accurate numbers to work with as far as the opening point of the thermostat.

 

[Larryjb]

We had a vehicle that wouldn't warm up, or barely warm up after driving. Some one had cut out the core of the thermostat. It's time to look at the thermostat, just get a new one. Unfortunately, it's a pain to change.

 

[93M6Formula]

203 is not "a tad warm". Its actually closer to normal.

Start your engine up cold and watch and the temp gauge to see what the highest it achieves until you all of sudden see it start to drop (which means your thermostat just opened up). WOuldnt hurt to ignor your temp gauge and hook up a scanner and get temp data from there while watching temp gauge to see the drop. Your scanner data temp may not respond fast enough for you to get accurate numbers to work with as far as the opening point of the thermostat.

203 is not "a tad warm". Its actually closer to normal.

Start your engine up cold and watch and the temp gauge to see what the highest it achieves until you all of sudden see it start to drop (which means your thermostat just opened up). WOuldnt hurt to ignor your temp gauge and hook up a scanner and get temp data from there while watching temp gauge to see the drop. Your scanner data temp may not respond fast enough for you to get accurate numbers to work with as far as the opening point of the thermostat.

I agree, what I mean I guess is that it was warmer than it usually is. The gauge was showing roughly "225" instead of "210".

 

[93M6Formula]

This is with that line basically clamped shut. This was showing about 203-207 on my scanner.

 

[Charlie207]

@Charlie207 posted a few pics in this thread. The restrictor is a small orifice built into the radiator fitting for the small return hose going to the surge tank.

Cold Case radiator

Somewhere in these threads a 45 cal Brass without primer installed was cited as a "perfect"fit restrictor. Is there a quick DIU for this? My aftermarket radiator ( Champion) also cools too well on cool mornings, and causes the same dash error. I have a zillion .45 brass laying around, and...

www.tahoeyukonforum.com

If anyone wants spent .45ACP brass for this mod, let me know. I'm happy to throw one or two in an envelope and mail them to you.

OD post-fireforming looks to be 0.478" which fit snuggly, but easily, in my GMT900 overflow hose.

I'll let you drill it out to your preference.

 

[93M6Formula]

I think I will probably just get a new thermostat again and test it this time before install. Kind of want to get a new GM pump too just to be sure nothing is wrong with it. All I know is it shouldn't take a 5.3 gasser longer to warm up than my diesels, that's why I bought a gasser again for winter lol.

 

[Doubeleive]

if you are going to do the thermostat then get a new oem radiator as well and be done with it. both are easy to do

 

[rockola1971]

If anyone wants spent .45ACP brass for this mod, let me know. I'm happy to throw one or two in an envelope and mail them to you.

OD post-fireforming looks to be 0.478" which fit snuggly, but easily, in my GMT900 overflow hose.

I'll let you drill it out to your preference.

View attachment 386692

Id rather you throw the magazine in a mailer and send it! I have all the .45 acp brass that I need.

 

[rockola1971]

I think I will probably just get a new thermostat again and test it this time before install. Kind of want to get a new GM pump too just to be sure nothing is wrong with it. All I know is it shouldn't take a 5.3 gasser longer to warm up than my diesels, that's why I bought a gasser again for winter lol.

Not alot to go wrong with a water pump. It can leak past its mechanical seal, impeller could come off its shaft (overheating would happen then) or the impeller could corrode away (overheating would be the symptom for that too).

 

[Charlie207]

Id rather you throw the magazine in a mailer and send it! I have all the .45 acp brass that I need.

Primary Arms had them for like $22 for a while.

 

[93M6Formula]

Not alot to go wrong with a water pump. It can leak past its mechanical seal, impeller could come off its shaft (overheating would happen then) or the impeller could corrode away (overheating would be the symptom for that too).

My worry I guess is that it's some super cheap aftermarket replacement that has some flaws, it's definetely not original. Wondering if it's an issue with the thermostat surface. Just spitballing at this point.

 

[rockola1971]

My worry I guess is that it's some super cheap aftermarket replacement that has some flaws, it's definetely not original. Wondering if it's an issue with the thermostat surface. Just spitballing at this point.

Another quick and dirty check is to squeeze upper radiator hose between your thumb and index finger on a cold enngine and see if you feel a surge of coolant trying to push your fingers apart. This should not be happening on a cold engine. If it is then it means the thermostat is stuck open (Before the engine is even warm).

 

[nonickatall]

How long did it take, at 32° Fahrenheit to get the temperatur in the middle of the gauge, when driving normal?

I would like to know to compare. My Escalate 6Liter needs minimum 3-4 Miles or more. What is normal on this engines?