Do you still have the flutter in the needle? 17 to 18 is better and closer to a healthy engine. You've replaced the timing set but not pulled the heads, correct?

 

Steady no flutter. have not pulled the heads, I am not a mechanic, the plenum was the biggest job I ever did. I thought they might be replacement heads because they had yellow paint pencil writing on them when I removed the intake.
PO was a chiro who bought it in SoCal and drove it up top the PNW. He said it was garaged and only used to haul yard stuff to the dump. If you have seen the pics it is pretty clean but I doubt he did any maintenance. People up here don't get the point of SMOG. One good thing about it is you know any vehicle you buy that passes it is not going to be a lemon in the motor department because the seller has to have the Veh pass a SMOG test to sell it. It is not as easy as you might think to pass a smog by faking things and with the system computerized since the early 90's, techs can't "help" you out as easily as some used to.
Took off the TB and the only oil I can see can be explained by the PCV valve.
This was an OE California vehicle, I now have a 49 state CAT on it but that should not affect all the pre CAT workings. Only one O2 sensor pre CAT.

 

If you're pulling 17-18 inches of vacuum and the needle is steady, you may just be dealing with a different blend of fuel. I've seen noticeable differences between winter and summer blend fuel in the past. My current driver has SkyActive technology (don't ask me to explain THAT) nd it doesn't seem to care. However, a heavy foot and different fuel may be the reason for different mpg readings.

 

My concern is the smell of unburnt fuel. Even with low MPG exhaust should not smell of fuel.