Smoke pouring out of vents

[BathiasRei]

Hope it’s going well!

Within the last hour my TJ started blowing smoke out of the ac to the point of having no vision in the cabin!

The story goes that I recently did an engine swap and had ac lines and everything disconnected so my system is free of Freon. Today I did a coolant flush and was testing/running the heater, which was blowing barely warm throughout flushing, thinking it was a clogged heater core. I then proceeded to go on a 1.5 hour trip running errands where I believe I may have accidentally left the blower running on the lowest setting during this time without noticing as I had the doors off. Well with all this said as I got near home smoke came pouring out like I had a smoke machine in the cabin!

Thinking my heater core popped and is now leaking since I don’t see any other leaks or anything touching the exhaust but I wanted some second opinions before I tear into it or drive her around but leaving the blower off. Coolant and oil levels appear normal so I’m wondering if it should be safe to drive to my usual parking lot about 10 minutes away or even to leave unattended since she’s still hot right now?

Edit: drove down the street and engine ran normally, blower was indeed on but set to cold and smoked lessened to the point of vision through windshield when turned off but still vastly visible as I drive.

Thanks for the suggestions!

 

[macleanflood]

Your luck absolutely sucks!

Was it steam or smoke?

I'm thinking you burned up some of your heater wiring. Seems like there's two posts a week about folks cooking switches or whatnot because the current through the factory wiring and switches is a tad bit much.

-Mac

 

[BathiasRei]

Your luck absolutely sucks!

Was it steam or smoke?

I'm thinking you burned up some of your heater wiring. Seems like there's two posts a week about folks cooking switches or whatnot because the current through the factory wiring and switches is a tad bit much.

-Mac

Im thinking it was definitely smoke as it smelled and looked exactly like I had bond fire in my climate controls / vents

I agree my luck hasn’t been good with the TJ after my old engine threw piston #5 but such is the price of a free rig

 

[DuckNut]

Turn the key to the run position and see if it returns. If it does, you can find where it is coming from. If it returns, it is electrical and you need to find it before it starts a fire but also why it did not blow a fuse.

 

[BathiasRei]

Turn the key to the run position and see if it returns. If it does, you can find where it is coming from. If it returns, it is electrical and you need to find it before it starts a fire but also why it did not blow a fuse.

For the most part the smoking has died down now with the car off, wondering if it’s ok to leave off for a bit while I bus back home to get some tools from my while off apartment before I go diagnosing?

 

[macleanflood]

Pull the terminals off the battery first.

Call non-emergency dispatch and ask for the nearest fire station. See if any of the on duty fire fighters will cruise over with a thermal camera.

-Mac

 

[BathiasRei]

Pull the terminals off the battery first.

Call non-emergency dispatch and ask for the nearest fire station. See if any of the on duty fire fighters will cruise over with a thermal camera.

-Mac

Had a friend bring me the tools instead while I watched the jeep, with key in on position nothing seems out of the ordinary… turned the blower back on to the lowest setting and no more smoke came out but still smelled like a plastic barbecue in the cabin once the air ran for 5 seconds. Maybe the heater core is leaking on and burning plastics? When the vents was smoking it was more so a white smoke similar to a tailpipe with a blown headgasket but was coming out at the rate and consistency of a fire. Not 100% though cause it was also hard to tell since it’s night and not being able to see.

 

[BathiasRei]

Had a friend bring me the tools instead while I watched the jeep, with key in on position nothing seems out of the ordinary… turned the blower back on to the lowest setting and no more smoke came out but still smelled like a plastic barbecue in the cabin once the air ran for 5 seconds. Maybe the heater core is leaking on and burning plastics? When the vents was smoking it was more so a white smoke similar to a tailpipe with a blown headgasket but was coming out at the rate and consistency of a fire. Not 100% though cause it was also hard to tell since it’s night and not being able to see.

Also just found small amounts of ash and soot spitting out of the air but no smoke after running the engine and turning the blower on for about 10 seconds or so…? Thinking a heater core leak onto an animal nest or something in the HVAC system since the rig used to sit before I got it

 

[macleanflood]

Maybe it's running so fast now something flammable fell on to a hot resistor or something hot?

Have you pulled the glove box and looked behind it?

Maybe the dash bezel and pull the screws on the HVAC controls and look at the connectors?

I've had my dash out two or three times now...if I didn't find the smoking gun (excuse the pun) I'd just keep pulling things apart until I did.

I suppose someone smarter than me would get out the wiring diagrams and start checking continuity and ohms. But fuck if it was smoking it can't be that hard to find.

When you upgrade to a paid membership you need to change your tag line to "Let the smoke out."

-Mac

 

[BathiasRei]

Maybe it's running so fast now something flammable fell on to a hot resistor or something hot?

Have you pulled the glove box and looked behind it?

Maybe the dash bezel and pull the screws on the HVAC controls and look at the connectors?

I've had my dash out two or three times now...if I didn't find the smoking gun (excuse the pun) I'd just keep pulling things apart until I did.

I suppose someone smarter than me would get out the wiring diagrams and start checking continuity and ohms. But fuck if it was smoking it can't be that hard to find.

When you upgrade to a paid membership you need to change your tag line to "Let the smoke out."

-Mac

Haven’t done the glove box, will do soon and definitely just pull the whole dash apart like you suggested. Thinking I’m going to let it sit in the back corner of the university parking lot (away from cars and trees) since I have to tend to some schoolwork tonight then see to it tomorrow… unplugged the battery fully and made sure everything was cold before I leave it to go back to my close- by apartment

The puns are great and I agree with the tagline choice

 

[macleanflood]

I changed the exhaust manifold in the back of one of the UOP parking lots on a 1984 Nissan Pulsar in, what 1996 or 97.

Took that car to Tahoe to with six new friends who bought me a lift ticket and rented me some skis in exchange for a ride. That was sketchy...way overloaded car in snow. Skiing in jeans wrapped in duct tape is fun.

-Mac

 

[DuckNut]

A couple things...

If it smelled like plastic it is most likely a wire - wire sheath melting or bare wire melting some plastic it was laying on.

Heater core leak would have smelled sweet and would not produce smoke, steam maybe but not smoke.

If ashes came out with the blower it is not heater core because wet ashes stick, not float.

You are looking for an electrical short.

 

[KennethS]

The above is exactly what I was going to say. An intense heat source produces smoke and ashes; leaking hot water does not do any of that.

 

[BathiasRei]

A couple things...

If it smelled like plastic it is most likely a wire - wire sheath melting or bare wire melting some plastic it was laying on.

Heater core leak would have smelled sweet and would not produce smoke, steam maybe but not smoke.

If ashes came out with the blower it is not heater core because wet ashes stick, not float.

You are looking for an electrical short.

Gotcha that does make a lot more sense, clearly I have a lot to learn still and some common sense to gain!

got about half way done with pulling apart the dash this morning, haven't found anything out of the ordinary yet, hoping to finish by tonight or tomorrow morning when I'm done with classes.

 

[chumpchange]

did you check the ashtray? there may be some sage in there.

 

[macleanflood]

How much spare change have you found?

I found about $3 in my TJ and a zillion pens from the OP. My wife's JK...took out the seats and found $8 mostly Canadian...

-Mac

 

[BathiasRei]

How much spare change have you found?

I found about $3 in my TJ and a zillion pens from the OP. My wife's JK...took out the seats and found $8 mostly Canadian...

-Mac

Surprisingly I haven’t found much behind that dash or around the ashtray besides a metal straw and drive in movie tickets? My gfs uncle that had the jeep before me kept her clean and sitting in his garage so I guess it checks out that not much was lost

 

[B1Toad]

My money is on the blower motor resistor. It's located inside the blower housing so a meltdown would put smoke out the vents.

 

[KennethS]

I found about $3 in my TJ and a zillion pens from the OP. My wife's JK...took out the seats and found $8 mostly Canadian...

-Mac

Isn’t that the same amount of US dollars?

 

[BathiasRei]

My money is on the blower motor resistor. It's located inside the blower housing so a meltdown would put smoke out the vents.

Finally had time to finish it today and you were right. Had the dash apart and the blower motor out and it looked like a rodent made a nest throughout the system… When I took out the blower motor the surrounding area was filled with burnt leaves and twigs .

Guess I’m just glad it didn’t catch on fire fully but wondering if I should replace my blower if it was getting hot enough to cause smoke?