Noticed my car smoking white out the exhaust and downpipe yesterday. Only change I've made recently is I've been topping off my Mobil 1 10w30 with Mobil 1 15w-50 over the last two weeks. Car has about a quart and a half of the 15w-50 in it. Smoke isn't constant, seems to happen with the car sitting idle for a while. Oil level is at the top, doesn't appear to be overfilled.

I bought a case of 15w-50 to fully change the oil this weekend but with this happening I think I'll go back to straight 10w-30 to see what happens.

Yes, the car idles perfect. There is no milky residue in the oil cap. As a matter of fact, last night I tried flushing air out of my coolant system (I currently have little to no heat) and while I was bleeding fluid all over my garage floor the coolant was of normal color so I think that pretty much rules out something wrong with the motor. I pulled my catchcan out as well since it had a collapsed line, not a drop of oil in it.

Any ideas of what else to check? My only other guess is my return line is backed up from too much oil maybe?

 

You shouldn't be mixing viscosity like that, it can possibly cause oil foaming due to things like different additives etc.

I hope you dont have a blown head gasket.. The lack of heat means you definitely have air in the system, how it got there is the big question.

Good luck!

 

check your return line. what size oil sending line are you using? are you running a resrictor?

 

I know why I have air pockets in the system. Not a big deal.

 

Generally changing weights shouldn't be an issues. If you think its an oil problem, just monitor your oil levels. If its not consuming oil, its probably not oil thats being burnt and causing smoke.

Whats the exhaust smell like?

 

Monitoring oil levels is problematic as a troubleshooting tool because my car is an AP1 and it burned oil stock. I would imagine it still burns oil on a regular basis. But, either way I do check the oil daily.

I can't put a finger on the smell. Its not an oily smell per say which first led me to coolant. But for coolant to be making its way in the exhaust I'd have to have a blown headgasket (which I'm not ruling completely out, oh the irony that would be) but at this point i'm 95% sure its not. If I can't resolve this today or tomorrow, I'll do a compression test just to double check the health of the motor.

 

wouldnt this be the issue, a collapsed line on the catch can will cause a restriction in flow, backing up, causeing excessive blow-by, and thus creating smoke........

 

If you got any friends as a mechanic, most usually have a tool that reads the coolant to see if any exhaust gas are in it. Its like a litmus test

See if you can use it to determine if the gasket is blown or not.

 

Also, pull the filter off the turbo and see if you can see any oil residue in the compressor housing.

 

Car still smoked after I replaced the line.

Ya, I'll check behind the filter today. No friends with the tool you're talking about though.