Hey everyone this is my first post here. I just started auto rx and I am about 1000 miles into it on my 2002 7.3 140,xxx miles. Today I have noticed that when I take off from a stop light the tailpipe will blow out a blue puff of smoke then black smoke will come out, any ideas why??? Thanks
I would think that if it was not whiffing blue smoke on cold starts prior to switching over to the slightly heavier Valvoline 10W30, it is unlikely that a valve guide is bad, or more likely a valve seal. It is possible that some crud is still dissolving out of the valve train and finding its way into the combustion chamber due to some crud slipping down into the combustion chamber. Kind of like the motor is still cleasing with the maintenance dose.
You can always switch back to the SuperTech 5W and see if this solves the issue. In my estimation motors with 146,000 on the clock, which have seen a diet of dino oil are best served by staying with dino, or mineral oil.
If the car starts up without blue smoke after it has been run during the day, then I find it unlikely that there is any serious valve guide wear.
