luyo

What is the right pressure with the engine on and with the key on and engine off??

HAILERS

With just the key to ON, there should be NO fuel pressure. Pump does not run with just the key ON.

With the engine at an idle of approx 750 rpm, the fuel rail pressure should be about 28-32 psi.

With the engine at idle, AND the vacuum hose disconnected from the Fuel Pressure Regulator, the fuel pressure should be 35.6 to 37 psi.

OR, with the key ON and the fuel pump check connector jumpered with the engine not running, the fuel pressure should be 35.6-37 psi.

That is all in the free, online Factory Service Manual that is downloadable from this sites FAQ thread...........along with how to set the TPS using two LED lights.

The fuel pump only runs if the key is HELD to Start............or if the engine is actually running.........or if the key is to ON and the fuel pump check connector is jumpered............or if the key is to ON and the vane inside the AFM is pushed aft at least a eighth inch or more (series four).

How to build the two LED light assy for checking the TPS is shown in this article:http://www.teamfc3s.org/info/article...odes/main.html Don't use any light other than a LED to do this or you'll burn up the transistors in the ECU.