1997 Civic Burning Smell

My wife’s civic has developed a acrid burning smell that seeps into the cabin and I am desperate to determine the cause.

We have noticed that the car must be warm and it only noticeable at 45 mph and above. The smell is worse the warmer it is outside. In addition, if we turn on the ac/heater/vent the smell will disappear. If I pop the trunk after driving for a while the odor is very strong inside but there is no hint of smell in the engine compartment.

I cannot replicate the smell in the garage but I ‘think’ I can smell it very faintly from the exhaust while the car is idling.

We have recently had the following work done:

1. Exhaust manifold replaced. (done by dealer)

2. Spark plugs, wire and distributor cap. (done by dealer)

3. All drive belts. (done by me)

It has been several months now and the smell has not lessened despite her daily commute. I have had two mechanics look at the car but of course they “dont smell anything”. Help!

After driving, feel the rims. If one of them is hot you could have a brake caliper hanging up and causing that brake to hold. If it is a front tire you will notice the car wanting to pull to one side. Because you smell it strongest in the trunk I suspect a rear tire. Another way to test is to put the car in drive and remove your foot from the brake but don’t accelerate. The car should creep foreword. If it doesn’t, goose it and release and it should continue to roll. If it comes to a stop on it’s own then you know your brakes are hanging up. Also check to insure your emergency brake is fully disengaged. This could be an intermittent problem so check the rims right after the commute when the smell is present

Ditto to Trout’s post…
but feel the rims CAREFULLY. A dragging brake pad can make a steel rim (if you have steel) very hot.

Well, I have not had a chance to actually feel the rim after driving but to be safe I had a shop check the brakes and there was no sign of the brakes locking.

Any other thoughts?

It’s great that you got the brakes checked. That’s always critical to not procrastinate on.

Since the smell is appearing in the trunk, I’m wondering of you have a rear wheel bearing going out. Feel the wheels anyway after one of these drives to see if one is hot. Also, jack up the rear wheels and see if they’re both spinning freely and without noise.

Yours is a FWD cehicle, and that or something cooking on the exhaust are the only things I can think of that might leave a burning smell in the trunk.