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Identify a smell

Noticed a smell like rubber burning about 40 minutes into driving my car today. When I turned off the heater it went away. Any ideas what this may be? Possibly the last legs of my heater melting away?

An oil leak onto the exhaust system will cause this smell. The heater brings in fresh air from the outside and the burning oil on the engine will cause this smell to be drawn in by the heating and ventilating system. I would suggest doing the following: warm the car up and lift the hood and see if you get this odor around the engine. If so, you need to track down the source or have a mechanic examine the engine. If you don’t get the odor, take the car for a ride, turn on the heater and see if you get the odor. If so, pull into a parking lot and sniff around the front wheels to see if you have this odor. If this doesn’t turn up the problem, I suppose it is possible that the heater blower motor or the blower resistor is burning out.

One other thought: this could be a one time occurence from something outside the car that was coming in through the heating system. I remember years ago on a family vacation picking up a terrible burning smell inside the 1954 Buick my dad owned at the time. He pulled off the road at the nearest safest point and shut off the engine. We opened the hood, but all appeared normal. When my dad restarted the engine, all the gauges indicated that all was well. We pulled back onto the highway and all was well for a couple of miles and then the smell returned. Again, we pulled off the highway, but left the engine running. When we lifted the hood, all again was fine–no burning smell and the engine was running normally with no visible smoke. We pulled back onto the highway and a couple of miles later the burning odor returned. Since the gauges were normal, we kept going. We finally saw the problem–a big diesel truck and semi-trailer was laying quite a smoke screen and we were picking up the exhaust odor from the truck. Another time, I was driving in town in the 1948 Dodge I was restoring. I was driving in town and suddenly the cabin was filled with a burning grease odor. I was at a busy intersection and couldn’t pull off the street. However the gauges were all in the normal range. Waiting for the traffic light, I saw the problem. I was right next to a steak house and was picking up the odor from the smoke coming from the steak house chimney.

Sometimes I’m so sad and disappointed by the world in which we live and then I see this. Thank you so much. To your second thought, I considered a different source, but my 17 year old said it was doing the same thing over the weekend. I recently had the oil changed, so maybe there is a connection. I will do as you suggest. Also, the heater blower motor for the back part of the car hasn’t been working for 3 years, so it could be the front one is now on its way out. At any rate, as you recommended, I’ll sniff around. Thank you again so much!

The fact that you recently had your oil changed provides another clue. There may have been some spillage during the change. So you have oil dripping onto hot exhaust components, and the blower fan is sending the fumes into the cabin.

If this proves to be the case, the situation will clear by itself in a few days. As a precaution, however, check under the hood to see if the oil filler cap has properly been installed.

" I recently had the oil changed, so maybe there is a connection".
I’ll bet there is a connection. Before you drive the car again, lift the hood and check to see if the cap is in place where oil is added. I’m wondering if a careless oil change person forgot to put the cap back on. I’ve had that happen. You don’t want to drive the car without that cap as oil can splash onto the exhaust system and if things are hot enough, you may have a fire.

It can be pretty common for oil to spill on the exhause pipe when they change the oil filter and that would smell when the exhaust gets hot. It shouldn’t really last that long though. In addition to checking the oil fill cap, the oil filter itself might be leaking on the exhaust. This can be catastrophic if you lose the oil in the engine. I think it might be worth taking it back and having them check for leaks. A rubber burning smell can also be coming from the serpentine belt driving the alternator etc.

Thank you everyone. I really appreciate it.