High fuel consumption

Thanks for the info. Being a novice can you explain CAT & MAF.

This '97 Rav4 gets the worst gas mileage I've ever seen. It's getting around 130-150 miles per tank. That's driving very carefully, no fast stops or starts, keeping speeds 60 and under. At highway speeds you can see the gas gauge move downward.
It has no codes set. And the plugs, distributor cap, rotor, and plug wires are fairly new. All the normal things like tire air pressure has been checked.
This car has had the engine and transmission removed a couple of times because of trans issues. So it's possible that the vacuum lines have been reconnected wrong, if that is a possible cause of the poor mileage.
The engine starts and runs fine, it just drinks gas like a car with a 12 cylinder engine.
A check of the timing shows it's off by a couple degrees, but the timing can not be adjusted on this engine.
Thanks for any help you can give me.

So would a donation help get this question answered? I could use some help, I'll give what I can.