Car producing white smoke after a dead battery

Mike1998
Tue, 07 Feb 2023 03:46:57 +0000
Maintenance/Repairs

I have a 2011 Subaru Outback. The car is 12 years old, but the battery is just under 2 years old. I parked the car at my brother’s house before leaving on an 18 day trip. On day #8 of the trip my brother back home needed to move the car and reported to me that the car wouldn’t start. This is unusual for the car as it routinely goes 1 week or 1.5 weeks without being started.

Doing a traditional jump start wouldn’t work, nor would the car start after it was plugged into the house via an extension cord. When I got home (after my 18 day trip was over) I was able to source the problem to an EXTREME level of corrosion building up on the battery. After cleaning off the battery the car started. It didn’t take much effort to start the car, it simply needed a clean. Car runs fine, sounds fine…

THE PROBLEM: The exhaust pipes are emitting very heavy white smoke + oder. If not for that white smoke I’d say nothing was wrong with the car other than the car not moving for 18 days.

Is this smoke something to be expected, some sort of buildup that needs to be cleared out, or is it a sign that something is seriously wrong? I turned the car off right after noticing the smoke and haven’t given it a chance to determine if it just needs some time to “clear out” a residue or if I’m on the verge of blowing some kind of gasket.

In the 18 days I was gone my brother probably turned the key 40+ times trying various methods to get the car running (jump starts & what not) and perhaps that caused some kind of buildup. The car was also outside for 18 days and in that time the temperature has had some extreme shifts dropping as low as -15 (F) for a few days and now we are in a warm streak with temperatures in the high 40s.

I’m hoping its residue buildup and the car simply needs some time to run and clean out the engine. Or is this something that needs a mechanic ASAP? I wanted to ask you guys for your advice before I attempt to let the engine run for more than the short time I’ve had it running.

13 posts - 8 participants