think i got a leak need help identifying issue

[BlueCollarTahoe]

been smelling here and there like a burned plastic rubber type smell through the vents. i thought it was the electrical lines ran through for the cb system getting too hot. i checked and theyre not rubbing against anything. did some searching and went looking for a leak saw this:


could it be this heating up? looks like is coming from the back of the radiator. its on the passenger side.

 

[Doubeleive]

Those appear to be the transmission cooler lines, the leak is very typical, probably not enough to cause a smell but maybe....you can get new ones from the dealer or online, rockauto probably has them.

 

[BlueCollarTahoe]

Those appear to be the transmission cooler lines, the leak is very typical, probably not enough to cause a smell but maybe....you can get new ones from the dealer or online, rockauto probably has them.

they difficult to replace? think the smell of whatever is leaking could be what i smell from time to time?

 

[Doubeleive]

I have only disconnected mine when replacing the radiator, they have a horseshoe type clip on them which can be a little tricky to get off without it snapping off into never never land to be lost forever but usually the new lines will come with a new clip so there will be spares, they come pre-bent and have to be fitted into place down to the transmission, how tricky that part is I don't know on these trucks I did some on my old trans am and had to bend them a little to get them in but it worked out ok. a sharp poker or very small flathead screwdriver will get the clips out and or a pair of small needle nose pliers may be helpful, once the clip is off you just pull the line out, you may have to jiggle it a little, some fluid will come out but it's only a little bit nothing to worry about maybe a few tablespoons at most. more fluid may come out down by the transmission, I would get underneath there and get a flashlight and follow those 2 lines and see how they fit in down by the transmission and that will give you a idea of what it will take. I don't think it will be that hard.

 

[M1Gunner]

They’re not too bad to replace. You may have to play with their placement a lil so they don’t rattle under certain engine load. Kinda sounds like a cat heat shield but not quite as high pitched.

I’d be willing to bet that is NOT the cause of the smell that concerns you though. That would have to collect up to a drop and then be blown up to the exhaust manifold just perfectly to cook that fluid. Even then for it to do it multiple times just right and still find it’s way into your cab enough for you to smell through the vents is extremely unlikely... not to mention give off the odor you’re describing.

Check your blower motor resistor for signs of over heating. That’s where I would start.

 

[M1Gunner]

And honestly, just my opinion, I wouldn’t worry at all about that “leak” let alone replacing those lines just yet that’s just minor seepage.

 

[BlueCollarTahoe]

They’re not too bad to replace. You may have to play with their placement a lil so they don’t rattle under certain engine load. Kinda sounds like a cat heat shield but not quite as high pitched.

I’d be willing to bet that is NOT the cause of the smell that concerns you though. That would have to collect up to a drop and then be blown up to the exhaust manifold just perfectly to cook that fluid. Even then for it to do it multiple times just right and still find it’s way into your cab enough for you to smell through the vents is extremely unlikely... not to mention give off the odor you’re describing.

Check your blower motor resistor for signs of over heating. That’s where I would start.

even if im not using the AC/heating system? i just replaced it cpl months ago. doesnt smell when i run it. seems to work fine.

 

[retiredsparky]

You could have a wiring issue where wires have rubbed against a strut under the dash, damaging the insulation. The burning smell more likely indicates an electronic module problem -- each module has its own power supply and the module parts are made to the lowest standards and still do their job. Switching power supplies are pretty reliable, but if the voltage regulator or a transistor or an electrolytic capacitor is starting to fail, you could get that smell.

The best way to find the source would be a small 12 volt fan installed in cardboard with a rubber or plastic hose to make a miniature vacuum cleaner so you can move the hose around under the dash and into the ducts to detect the odor.

Since you said the smell isn't there when you run the heating system, it can't be the fan motor.

Another possibility is a mouse nest in the duct work, but I don't know how they would get in there unless they come through a rubber grommet in either the firewall or the floor and then chew their way into the duct. Mice usually prefer to nest on top of the engine, under the plastic cover.