My 1992 4runner 3.0 V6 is having an issue where sometimes after its been running for a while I will shut it off then go out and start it shortly after and it will start fine but idle around 100 rpm then die, if i give it gas it falls on its face and lately ive been getting terrible gas mileage (worse then a normal 3.0). I was thinking maybe a dying fuel pump. Any ideas?

 

Start with the basics, test fuel pressure, search for codes, compression test and make sure you have spark on all cylinders.