2001 suburban saying its overheating but it's not

[Damuskoopthagreat]

I got a 01 5.3 suburban 2wd that has no cats. In the message center I continue the get a messege of check coolant temperature/engine overheating. The temp gauge will bounce back and forth but the engine isn't hot nor the coolant. When this happens it runs horrible, no power, no speed and misfires. This started happening after I recieved a low engine power in the message center and determined it was the cats. So i went cat-less. I have no 02 sensors. Somedays I can drive it and its fine. No error codes. Then others when it runs bad I will get code P0117, P0157, P0300, P0420 and P0332. Even when I get the codes it's still not overheating. Just runs bad. Any help appreciated.

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

My first question is how did you confirm that the motor is in fact not overheating.

My initial thought is that you may have a failing temperature sensor, that may be causing this issue. I know that on my 07 Denali (I know, it is a different GM platform than your truck), when the coolant temperature went too high due to a heater hose shredding, the motor's computer automatically went into a 'limp' mode, limiting the motor's output and driving *******-t-y, in an attempt to save the motor, and a large number of codes were thrown.

Other folks with direct experience on your truck's GM platform will chime in.

 

[Damuskoopthagreat]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

My first question is how did you confirm that the motor is in fact not overheating.

My initial thought is that you may have a failing temperature sensor, that may be causing this issue. I know that on my 07 Denali (I know, it is a different GM platform than your truck), when the coolant temperature went too high due to a heater hose shredding, the motor's computer automatically went into a 'limp' mode, limiting the motor's output and driving *******-t-y, in an attempt to save the motor, and a large number of codes were thrown.

Other folks with direct experience on your truck's GM platform will chime in.

Thanks for the reply. I appreciate the help. I replaced the temp sensor and thermostat. I was also able to remove the coolant reservoir cap coolant wasn't bubbling. Engine was quiet and not knocking