So this was my very first time with the Lady at that altitude! Going up one of the passes just before the Ouray, I noticed a lot of black smoke.. thought that was ok.. black is always fashionablePretty common to get smoke at altitude with older Toyota diesels. My understanding is that direct injection and mechanical fuel pumps with no load are still fueling for the current RPM, but with no air introduced combustion does not happen, and that is why you see the white/blue smoke when going downhill using engine braking. Once you add air/throttle to the mix the combustion cycle happens and black smoke comes out again possibly with a soothing backfire!

