Truck smells like burnt popcorn - 2005 GMC Sierra

You need to get this checked by a good mechanic SOON. Burning smell could be something simple or something Dangerous! Could you describe the smell? How strong is it? A 'Burnt Plastic' smell could be a serious one as this could be a wiring 'short' which if not sorted could cause an engine fire. **HOWEVER** Check the obvious stuff first!
Sometimes when you have topped up the engine oil any small spills can heat up with the engine and cause a smell. Usually a 'musty' burnt cooking oil smell
A sweet smell could be coolant. You can get this if a radiator hose or the radiator is leaking. You sometimes get this smell if the head gasket has 'blown'.

does this only happen at home? If it does then get down to the level where you lay your head and look around the area or the room and find something that may have been burnt before or may have a burnt smell in the wood like a nightstand or dresser or the room you're sleeping in might have had a fire one time or something on a low level and when you stand up you don't smell it cuz its not at that level. oh also if you're laying in the proximity of your kitchen stove there's a good chance that something burnt inside there one time and you might be smelling that.

I think I just answered your question posed a different way. This post is worded a little different though. It makes me wonder. Do you mean when you have the vehicle running and you press the gas it doesn't move for a bit then does? To be more sure of the answer I gave you before I suggest you pull the dipsticks for your fluids again and smell them. If any of them smell burnt post back again with which one or ones. If my first diagnosis is right your transmission fluid will either smell burnt look burnt or both. By looking burnt I mean it will be a dark and brownish kind of red instead of a more translucent bright and vibrant red. The smell well it smells bad and kinda burnt. If you have any new fluid you would definitely be able to tell the difference. For the engine oil, it can also be burnt and again you would tell the difference by the smell but it is harder to tell by the look. It would be jet black and you might even see bits of metal if you clean it off the dipstick with your fingers then rub them together like you were signing money, money, money (which is what either the engine or the transmission is going to cost). Again if you speak of it only doing this when everything is warm it implies the transmission. Hope these answers help and I hope your day gets better! Still willing to answer if this doesn't help and you have more questions and answers.

The A/C control head is known to go bad on those vehicles and cause those problems. The panel that it is mounted to is easy to pop off, then the a/c controls screw to the back side of the panel.

check ur trans fluid to make sure it is full if low add fluid -look and smell the fluid should be dark burgundy not brownish and should smell like oil not a burnt smell u did not say how many miles or if the filter has ever been changed if it smells burnt or is brownish change filter also if high mileage change also

This part of the transmission gear work the hardest because it the first move to an accelerated gear change. I hope the problem is not too far gone. Check the level of the transmission fluid, not just that, check the color n smell. If it smells burnt u have burnt clutches. If however its more brownish than the original color n no burnt smell. Just drain n replace oil then see if it improves. If it doesn't improve, run a scan on it, it may also be the shift solenoids acting up. Worst case scenario is burnt clutches. I hope it doesn't get to that.

If the pump is starting to seize up, the belt maybe slipping on the pump pulley, causing the burnt rubber smell.

Either your Fan motor is faulty or the fan control resister assembly is burnt out, either of those will cause the smell.

sounds like it could be electrical then... have you done any changes to the electrical at all? rewiring, changing headlights, etc? I had a similar smell when I changed my headlights... new headlights were defective and were melting the housing and harness...

your heater core has gone out, thats why there is no heat and thats from leakage of antifreeze. Usually when you can smell burnt antifreeze it usually points to a blown head gasket or cracked head, smell your exhaust and if you smell antifreeze theres your culprit