Have Toyota Questions? Ask a Mechanic for Answers ASAP
This sounds like a lack of fuel and could be a lack of fuel pressure from the electrical pump at the tank.
1st thing to try is to remove the fuel filler cap and then flick the ignition on whilst listening for the brief ‘buzz’ of the pump
If the connections to the pump are corroded or damaged then the pump could stop at any time or could not be running at full speed. Check that its relay switches in and out and the relay contacts are clean and bright – replace the relay if in any doubt and do the same for the fuse,
Ideally measure the pressure at the injector rail (should usually be around 3Bar / 45psi +) and if this is low check the pump as described and also consider changing the fuel filter as if this partially blocked this too will reduce pressure.
in that case then you need to plumb the gauge into where the fuel line is fitted onto the end of the injector rail
ok if you have a voltage drop to the pump then its very likely not running as it should
try running a fresh wire directly to the pump from the battery to see if this fixes things
if it does then I'd consider making the new wiring permanent and splice it into the original exit socket on the relay , ensuring that you cut the original wire
do you still need help?
Bear in mind that the site takes a deposit from you at the beginning and this is held by the site until you rate my answer at which point the cash is split between the site and the expert. I am only paid for my work on this question if you rate my answer, using the star system at the top of the screen. Please do not forget! Thank you