fuel and torque problems, HELP!!!

[Jack m]

Hi guys,
I've got a 1991 4runner with the 3vze engine, it has absolutely no torque and uses a ridiculous amount of fuel. Im getting like 200ks to a tank. The engine has no mods and is 288000kms old.
i have a 6inch lift and 32s. They are the only things i could think of that make fuel consumption and torque a problem. but i cant get up any hill really without being at about 5-6000rpm. It idles and starts fine, it doesnt blow any black smoke. I couldn't imagine it is running lean as it chews through the fuel more than it should. Once warmed up it does sometimes start to idle bounce. Please help me out as im lost
this is her

Cheers
Jack

 

[77'911]

Those wheels and the heavy bumper probably don't help things any, but here are a few things that came to mind:
1) check timing, make sure the t-belt has not jumped a tooth
2) check fuel pressure (rest and running)
3) if the fan clutch has never been done, replace it
4) if the o2 sensor has never been done, replace it
5) check the cooling temp sensor (under intake)
6) change out pcv, and check for vac leaks
7) change out t-stat, if the old one is sticking(open), the truck will be in cold run mode much longer then needed. This wastes a huge amount of petrol.
If it has not been done, do a basic tune-up, plugs (NGK coppers) and filters (air and fuel). I don't know if they are using ethanol in the fuel there, but in North America it has had a big effect on these old trucks, loss of power and mpg, with component failures. Hope that helps.
regards

 

[Jack m]

Those wheels and the heavy bumper probably don't help things any

its an alloy bull bar so its super light but defiantly everything you have pointed out is very good and il be having a look at them all. im also going to check compression.

cheers
Jack M