Hey guys,
This is a long shot, but wondering if someone may have experience with it.

Have a 1996 OBS, bought the truck in 2005. Im sure most of you understand when I try to describe the smell of diesel exhaust as sweet, almost pleasant. My truck had this smell when I first bought it. Since then its been through every scenario a dumb first time owner can be found in, I have learned, we all have learned.

Fast forward to 2016, and the truck doesnt have that nice smell of diesel exhaust anymore. It is much more harsh, is not 'sweet' at all, it actually burns in your nose a bit when you back into garage and have to hang out with it for a couple mins. It has bothered me, but the truck runs great still. I thought it may have something to do with the ULSD, until I walked by some older 7.3 ambulances some time ago and was reminded how nice my truck used to be...

Im bringing this up now because something has changed with the weather being colder. When the truck first fires up in the AM on particularly cold mornings, it smells like it used to, the nice smell of diesel. Once the truck has warmed up and I reach work, back to the harshness again. Does not do this until it gets fairly cold, below freezing. Anyone have experience with this before?

-Krause

 

Different fuel emit different smells, bad injector O rings, bad turbo seal, blow by emitting oil into the intake and low compression. All of this will let the exhaust smell funky.

 

I was about to say the same about injector o rings. Mine was smelling a little burned/acrid one day. I switched to different injectors and when I pulled the old ones, the seals were cracked and old. I could've just replaced the o rings but I said screw it. Went with stage 1s.

 

Since we texted the other morning I have thought about this deal several times.
I honestly have a feeling it's all in the tuning. Just like the gearhead tuning issue you had. It's either amount of fuel being a tad rich cold or maybe lean when warm maybe.
That's my .002 anyway