Fuel Consumption On 1986 Mr2

[hazchem]

Hi folks. First time post here. Just bought a 1986 1.6L MR2 about 3 weeks ago. Amazing condition and has been well looked after but I think it's going through too much fuel. I've managed to work out that I'm only getting around 22/23 MPG and I'm pretty convinced that's a bit low! When I looked at the car I noticed the engine ticked over at about 1800RPM for about a good 5 or 6 minutes after it is started and then settles down at around the normal 900RPM but upon driving it over the last few weeks I have noticed that there can sometimes be a smell of fuel when speeding up and accelerating, thought this might just be normal at first because of where the engine is and the type of car it is. The car is garaged at night and there is no sign of any leaks and no spots beneath the vehicle that points to any fuel problems. A couple of mates said it could be needing a good tune up and that I should take it to the garage, but I don't want to do that right now and start spending a fortune on a car that I just bought and seemed to be in excellent condition. There is tons of paper work with the car and it has been fully serviced every year all the way through it's life so far. The oil in it is golden and apart from a small bit of rust on one rear wheel arch and a small bit near the rim of the T bar glass roof panels (which I intend to have fixed) the rest of the car is in top nick, so I know it has been well looked after.

Does anyone know what the MPG consumption should be on this car and does it sound like a simple tune up would sort me out or are there others areas I should be looking into?

Cheers for any help.