2001 5.3 Engine Wont Warm Up

[Catman59]

Guys I just bought a 2001 Tahoe with a 5.3. It was stolen and piled up so I put a new radiator , condensor etc in it. The problem is that it wont get over 165 degrees. I know it was running normal for a while , but just lately doesnt want to get up to 195. I just put a new Murray thermostat in it this morning , but doesnt make any difference ? Anything else to check ? Thanks

[Nytemare]

Guys I just bought a 2001 Tahoe with a 5.3. It was stolen and piled up so I put a new radiator , condensor etc in it. The problem is that it wont get over 165 degrees. I know it was running normal for a while , but just lately doesnt want to get up to 195. I just put a new Murray thermostat in it this morning , but doesnt make any difference ? Anything else to check ? Thanks

Check the temp sensor...it could be busted and not reading the right temp.

[WaterGuy]

Air pocket?

 

On my 5.3 I have to fill it up using the upper rad hose.

[Catman59]

Air pocket?

 

On my 5.3 I have to fill it up using the upper rad hose.

 

Would an air pocket cause low temp ? I took the small 5/16 hose off the tank and it runs clear. I have cracked about every hose coupling. Is there a special way to bleed it ? Thanks

[minibike132]

Air pocket?

 

On my 5.3 I have to fill it up using the upper rad hose.

 

Would an air pocket cause low temp ? I took the small 5/16 hose off the tank and it runs clear. I have cracked about every hose coupling. Is there a special way to bleed it ? Thanks

 

 

 

Air pockets make it run hot, not cold.

[Black02Silverado]

Do you have access to and IR thermometer? If so check the temp on the engine block, hoses and radiator with it once you have the truck up to operating time. Sounds like a bad gage or sensor. The only other thing is the thermostat could be bad. You can pull it out and check to see when it opens in a pot of water with a good thermometer in the water. Other wise the IR thermometer should point you in the right direction.

[Catman59]

A new twist. I drove to a Thanksgiving today. 60 mph it runs 170 degrees. 70 mph it runs 175-180. 75 on interstate 195 like it should !!!!! When I slowed for the exit ramp it drops back to 175 or so then back to 195 at cruising speed.

[Nytemare]

Hmmmmm..sounds like a grounding problem....change the sensor and see what happens.

[WaterGuy]

My 90 Astro van did the same thing. The faster I went the hotter the temp. I'm doing 80 and the temp is bumping the red zone.

 

Turns out it was the radiator. It was almost totally clogged. Not the inside. THE OUTSIDE. Could barely see thru the fins. Now the A/C was completely clear. I'd figure that the dirt would get trapped there first. The dirt was IN the fins not in front of the fins.

 

Installed a new rad and now I can hear the fan pulling the air thru the fins. Never knew it could be so loud.

 

May not apply to you but it will to somebody some day.