Okay, new problem, the engine is overheating

[exp500]

One suspect is idleing after overheat indication not cooling the motor quickly. Check time to overheat, idle vs say 2500 rpm. If it wasn't overheating before water pump, that is 1st suspect. 2nd is radiator clogging, 3rd is lower hose collapse- does it have a spring inside it? You have to narrow down your possible suspects list as logically as you can and as easy as you can. Was the coolant always clean?.....Pressure test is a good starting point. Two 1/8 holes drilled in thermostat is also one I recommend for everyday use.

 

[Rummel6]

I was thinking it was the cap not holding pressure since the fluid drops with it on or off and it seems to be letting radiator vapors come out of it when it’s hot but this danm thing is only 6 months old to not sure how often they fail

 

[Geotrash]

I was thinking it was the cap not holding pressure since the fluid drops with it on or off and it seems to be letting radiator vapors come out of it when it’s hot but this danm thing is only 6 months old to not sure how often they fail

It's worth replacing. Simple things first.

 

[Rummel6]

Is the cap leaking like that a symptom of the rad fluid dropping when I rev the gas

 

[GoToGuyRon]

If in park, idling with rpm increase a slight drop in water level is not unusual. With the new parts, failure of these is odds are less likely but not unknown. You have no heat at heater outlet? Are heat core inlet and outlet hoses temp correct for indicated engine temp? Is thermostat working correctly, failed open will not transfer heat causing overheat under load. Thermostat installed backwards? Cylinder combustion leaking into water jacket under load? Get test kit for gases in water. Ensure no collapsed radiator hoses. Proper waterflow through radiator. No buildup. No sticks, dead birds, dog fur, grass small rocks in radiator fins look close shit is small and gets packed in between fins. Pressure test whole cooling system. Pressure test cap separately. Heater core can act as a sediment pond. Even keeping good cooling maintenance, can still lose some efficiency.

 

[GoToGuyRon]

The problem it appears there are multiple condition issues. That don't seem connected. No heat in heater outlet. Hvac control head, blending doors, no or reduced flow through heater core. ( did you pull hose off heatcore return, good coolant flow?) Without being there my first easy idea is cap or thermostant failed open or no thermostant, resulting in no temp control. But that conflicts with no heat. That brings you back to similar but separate problems. Time to work on sons school commuter POS. Good luck.

 

[Rummel6]

So found out today when it overheated the top radiator hose
Is stiff as hell

 

[ivin74]

So found out today when it overheated the top radiator hose
Is stiff as hell

Either the water pump or thermostat is bad.

 

[Rummel6]

I just replaced the thermostat again so I guess the pump is all that’s left was worried my head gasket was leaking because I just did the dod delet 8 months ago

 

[Geotrash]

I just replaced the thermostat again so I guess the pump is all that’s left was worried my head gasket was leaking because I just did the dod delet 8 months ago

You can rule that out with a leakdown test. I have lots of experience with head gasket issues in other makes of cars. The symptoms you're describing are classic when the breach is between the combustion chamber and the water jacket. It's worth performing the test before you replace the water pump.

 

[Rummel6]

Water pump was already replaced when I had the dod delete also I notice the top hose was stiff and bottom was not wouldn’t that mean the radiator is bad has 196k on it

 

[Geotrash]

Water pump was already replaced when I had the dod delete also I notice the top hose was stiff and bottom was not wouldn’t that mean the radiator is bad has 196k on it

It could mean that the radiator passages are partially blocked, yes.

 

[avalonandl]

You didn't mix Coolants did you....i.e. green and orange....very bad....

 

[Rummel6]

I did switch to yellow when we did the dod delete but I had read that 2011 Tahoe the coolant color was the new style and the yellow was any make any model

 

[Rummel6]

Pretty sure it’s blown head gaskets cause overflow smells like exhaust so gonna try the blue devil pour n go

 

[exp500]

Since you are shotgunning I'm gone.

 

[Chris Z]

Pretty sure it’s blown head gaskets cause overflow smells like exhaust so gonna try the blue devil pour n go

You can rent a cheap colormetric kit that tests for combustion byproduct in the coolant from most auto stores.
Could be worth the 10 mins of diagnostics before you dump the blue devil in and can’t go back, lol.

 

[Geotrash]

Pretty sure it’s blown head gaskets cause overflow smells like exhaust so gonna try the blue devil pour n go

So you've received the advice several times to perform a couple of simple, definitive diagnostic tests, but you haven't acknowledged any of them, and are continuing to take steps to "fix" something, but you don't know what yet. I understand the desire for a simple answer and a quick fix, but then why did you come looking for advice if you're going to ignore it? It's your truck so you do you, but a proper diagnosis and repair will be a 100% sure and permanent fix. Putting some chemicals in your cooling system is at best a 60% possibility of fixing a coolant leak, and it will be temporary and will also likely have other consequences.

 

[wsteele]

So you've received the advice several times to perform a couple of simple, definitive diagnostic tests, but you haven't acknowledged any of them, and are continuing to take steps to "fix" something, but you don't know what yet. I understand the desire for a simple answer and a quick fix, but then why did you come looking for advice if you're going to ignore it? It's your truck so you do you, but a proper diagnosis and repair will be a 100% sure and permanent fix. Putting some chemicals in your cooling system is at best a 60% possibility of fixing a coolant leak, and it will be temporary and will also likely have other consequences.

You said it better than I ever could, spot on.

 

[Rummel6]

It has 197k on it not gonna play doctor on a Chevy pos don’t think I would ever buy one of there brand again nothing but money pits I’ll just go back to a Ford before sinking more money into this thing, even if it is a head gasket or block not worth the money to fix it