What causes a 4runner to not get enough gas?

Check the mass airflow sensor had the same problem on my bravada. Disconnect the electrical plug to it and see if that help.

Sounds like you have a fault in the coolant temp sensor circuit. If the PCM does not get the proper engine temperature, it will have trouble delivering the proper fuel charge to run the engine.

The other possibility is either a plugged fuel filter, or a weak fuel pump. Check your fuel pressure, and if you haven't serviced the fuel filter in a while, start there with a new one and then do the fuel pressure test next, followed by the coolant temp sensor, but you will need a scan tool for that.

SOUNDS LIKE UR TIMING BELT MAY OF SNAPPED,BEING IT
DIED WHILE DRIVING.

So it does turn over but want start right? Is it turning over slower but want start? Or is it turning over the same speed...Need more information.. Try this....The next time it want start...Loosen the gas cap...Sound crazy? ..lol. The car might be vapor locked...It's when your gas tanks pressure becomes greater than your gas pump..Worth a try....So the car cranks up runs good until it shuts off...Well it's not a fuse..or the on board computer...Because it would never start back...It's not a ground...Nothing would work..It wouldn't turn over at all..It could be a fuse link...There little tiny wires that act as a fuse... Sometimes you can move the wires and it will start..When it want start also check to see if your getting fire..Bad electronic ignition not sending enough spark...Of course it could be the ignition switch itself..Hope this helps...Something for you to check

If it starts, but won't stay running, it is either losing ignition or fuel after it starts. There are literally hundreds of reasons why these two things could be occuring. The vehicle needs to be diagnosed to 1. determine if it is an ignition system problem or if it is a fuel system problem. 2. determine what is actually causing the offending system to fail. It could be something simple like it is just out of gas or it could be something a lot harder to diagnose like a failed engine computer.

Is there power going to the starter, if so then check all the grounds. If not then you have a bad ignition

Carbon build up comes from rich mixture or weak ignition. This will cause misfiring, hesitation and hard starting. To fix the problem, change the plugs and use a plug that will produce a higher heat range. Which means it has a hotter firing/ignition when combustion. This will burn the excess gas that causes the carbon. Be sure to check the plug wires to make sure you don't have spark jumping. (check at night with engine running). Also be sure the air filter is clean.

had a similar problem with with my 4runner.replaced most of the fuel and ignition systems with no luck.finally traced the problem to a bad connection between the main relay and the fuel pump.there's a wire harness connection between the back of the gas tank and rear axle.I just replaced it with a solid run from the fuel pump and the relay.haven't had any problems since.

CHECK FOR SIGNS OF MICE IN AND AROUND THE FUSE BOX AND AIR CLEANER AREA. SOUNDS LIKE A CHEWED WIRE OR 6