e60rider

Recently i have been seeing white smoke coming from the car exhaust and the exhuast has a coolant or window cleaner type(the blue bottle spray) smell, and my front o2 sensor has a heater issue (code : P0135). Now when the car warms up after driving the smell is usally very minimal to none. I have checked the coolant level over the past few week's and the level is perfect (no exhaust smell in coolant either). So i was wondering if i should just replace the O2 sensor (bank 1 sensor 1) or is there a problem i need to fix beside O2 sensor?

I have 105000 miles nearly, so i think a failing o2 is okay at this mileage? Could the o2 cause this coolant like smell?

Please give me your opinion . Anything will help. (the smoke maybe due to cold weather, today was -19 Celsius

pcy

Open the oil filler cap and check if the inside of the cap has any peanut-butter-looking goo.

Which model is your car? I6, V8?

DanL

+1. Unfortunately, it sounds like you may have blown the head gasket and that killed your O2 sensor(s). A blown head gasket is usually caused by the engine overheating. Check inside the oil filler cap as pcy suggested. A peanut butter / milk shake looking build up could indicate a blown gasket but it could also be caused by cold temps and short trips. The next step is to do a compression test. Good luck!

e60rider

Okay, let say it is the head gasket wouldn't it cause all sensor's to go bad? Also, i checked my filler cap and it look like perfect engine oil. But i did notice the coolant level to be high even though the engine is rock cold!? Should i remove excess coolant?

e60rider

And sorry its a 528xi i6 2008

e60rider

Just check the oil cap had something white near the edges ?

FormerE30Owner

Looks like there is no problem. At those temperatures, some of the crankcase vapours (water, oil) might condense before being returned to the engine. A small amount of white 'something', probably frost, does not indicate that you have a coolant leak, especially since the coolant level has not dropped. A brownish, peanut butter colour goo does, however, point to a coolant leak, especially if the coolant level falls.

I would still keep an eye on the level however.

The grey smoke (vapour) and its odour in the exhaust sound normal to me also, considering the cold weather.

None of this should be connected to the sensor problem.

Salut, Bob P.