Former VWDieselParts.com Forum

Well after my major coolant system overhaul, I drove up and over the Rockies, and noticed black smoke billowing out my tail pipe. I immediately called the guys (Wolfsberg Auto) that did my coolant work to ask them for advice. They said that was a pretty normal thing for vehicles operating at higher elevations.

I went through my own diagnosis and felt that it was a pretty reasonable answer. The smoke only came out of the tail pipe only when the engine was working harder (like driving up and over mountain passes) while I had the gas pedal pressed all the way down. I figured the combination of lower air pressure at higher elevations and greater load was causing unburned diesel fuel the come out... just like when you start the car in the winter. But what about the Black Smoke!? Doesn't black smoke mean the engine is burning oil?

Well, I also asked Wolfsberg Auto to change my oil when it was in their shop and they said they put in 5W-30 synthetic. I was told to use 5W-40 by my mechanics back home, but Wolfsberg said there would be no difference. Hey, they're the experts right? Well what do you Folks think? Does the lighter weight oil make a difference? Does the oil viscosity play a role in the longevity for the engine?

I've been noticing the smoke more and more since the work was done last month on CO. Now I'm in Bend, OR and today I noticed a considerable amount of smoke while pulling out from a Stop Sign in first and second gear. WTF? My engine oil level is slightly lower than before too. Well I hope there is some advice out there. Thanks for reading everyone.

Dave

It is true that more black smoke will occur at higher elevations. Black smoke is not typically burning oil but rather an over-fueled situation. Blue smoke is burning oil. 5w-30 tends to be too light for these engines, especially if they have any considerable miles. Do you have an oil pressure gauge? Has the light come on at all at idle? Is the smoke that you are seeing present throughout the range of the accelerator pedal or only when it is floored? Any air bubbles in the fuel entering the pump when running?

Andrew

Thanks for the advice Andrew. I do not have an oil pressure gauge. I plan on getting an oil pressure gauge and tach in the near future but for now I'm relegated to the unknown. I'll change the oil and see what happens. Thanks!

Has anyone ever had any other experiences with black smoke?

When my 82 Vanagon diesel was new it would pass black exhaust going over highway 80 in the Sierras. Then it cleared up until 20 years later. This time the cause was the injectors. Bought rebuilt injectors, torque wrench and socket and replaced them myself in 2008. Exhaust has been clear since. This Westfalia camper has seen some fun times, taking me canoing, cycling, camping, even was a home away from home when my girlfriend evicted me, .

Hey Thanks for sharing. I'm putting in a new injector pump and new turbo injectors, maybe that will fix the problem. Thanks!

I have to say the injector replacement had an immediate effect on getting rid of the black exhaust. There might be a "set in" period for rebuilt injectors, because it seemed like over the following year the engine became quieter and ran smoother and had more power. I could get up the Indio grade in 4th gear and still doing 50 to 55mph. Previously i had to downshift to 3rd and crawl up at 35 to 40. Now i am working on a headgasket oil leak. That is not going to be so simple.