05 Subaru Outback producing burnt smell

Hi,



For the last month or so my car (2005 Subaru Outback LL Bean) has been producing a burning odor. It smells like air out of a latex ballon that has been burnt.



I took the car to my mechanic but was unable to reproduce the smell. He asked if the car only produced the smell going uphill as it could be my coolant leaking. Since then I have noticed that the car does in fact produce the smell primarily, if not exclusively going uphill. But coolant should smell sweet not burnt?



Anyways, heres hopin the car talk universe can solve my problem.



Thanks

– Sean

When you get the smell, pull over and open the hood. Look for some smoke or steam and see if you can locate the area it is coming from. Something is leaking and when the fluid contacts hot parts on the engine is producing the vapors you smell. It could be coolant, motor oil, or some other fluid. Use your eyes and follow your nose and see where it leads.

Is your Subaru a standard or auto transmission? Your smell could be a worn out clutch if you have a manual trans.

Check the engine area for a oil leak that may be dripping on the exhaust system. That makes a bad smell when it happens.

The smell could be exhaust gas and coolant due to a head gasket that is only leaking under maximum pressure.

Thanks for the replys… much appreciated.

On my way up to the mountain once I pulled over and open up the hood but didn’t see anything. I also tried following the smell which led me to the front driver side wheel, but again, I couldn’t see anything.

Last night I had a weird incident happen. I was driving up a big hill at night and missed my road, so I hit the brakes pretty hard and reversed back to the road I had missed. After reversing I noticed a tremendous amount of liquid on the road under my car exactly where I had braked suddenly. The roads were all dry and I looked to see if my car had been leaking liquid the whole time, but the road behind me was dry. It was only when I braked suddenly did all the liquid show up. You can see the pix here:
1 - http://goo.gl/vrv2J
2 - http://goo.gl/yaggc

I’ve tried reproducing the situation but haven’t seen any leaks under my car since.

Any insights would be appreciated.

Interesting pictures. The first one looks like fluid from both sides of the car wheel width apart. Check all the fluids of your car, including the level in the radiator when cool, not just the overflow jug. Do you have a temp gauge, if so is it reading normal?

I can only assume that the liquid shown in the pictures is coolant and it accumulated somehow under the radiator possibly. There may be a small leak near the bottom of the radiator or one of the coolant hose connections. The amount shown is pretty substantial so you should be having to replace coolant. Have you checked the coolant level? If it is low then you most likely have a leak in the coolant system.

Get the car to a mechanic and up on a lift to check it out. Pictures could be liguid from the car or perhaps the surface of the road was affected by the hard braking.

Not likely brake fluid, your brakes won’t be working.

If it is trans fluid that’s not good news for the trans.

You should investigate and solve this mystery right away.

I had the same problem with a smell in my 2004 Outback, and it was a leak in the CV boot on the axle that was spraying grease on the exhaust system. This is particularly common I have read on the front right side since it is near the exhaust system, and the boot gets hot and fails more quickly.

Unfortunately the standard procedure is to replace the half axle since gunk from the road can get in and ruin the joint. From what my mechanic told me, due to the labor involved it is better to replace the axle rather than just the boots.

Nice work kridnix!

I got my car back from the mechanic last week and they weren’t able to find anything serious other than a leaking CV boot, which they didn’t believe was causing the problems. Thanks so much for connecting the dots for me and for the tip on replacing the axle.

Thanks again!

Hi kridnix,

I had a quick follow up question. Is the CV problem serious? Meaning, is this something I should fix immediately or something that could be dealt with once the problem becomes worse? Also could you let me know how much your repair bill came out to?

Thanks again!
– Sean

Did you check to see if that liquid appears to be water? Any chance this could have been water from clogged rear drains for the sunroof? Slamming on the brakes shifted that water forward maybe and then out the front it goes?
The same logic could be applied to water buildup inside floor pan rails, etc.
There’s just too much liquid there in my opinion for it to be anything else.

As to the smell, that could be dripping oil, coolant, or CV joint grease burning off of the exhaust. It should be difficult to find the source of that smell. Hopefully it’s not weeping head gaskets.

Hi Sean, your valve cover or oil pan gaskets could leak onto the exhaust. I have an '00 Outback and had leaks at the valve covers, oil pan gasket and oil separator cover, high mileage though, 215k. In '04 the oil separator cover was changed to steel and shouldn’t be a problem on yours.