car will start for about 3 seconds then shut off .. if i jump two wires it kicks on the fuel pump and i will stay running ..

i replaced the relay and checked all fuses .. when i first turn the key on the you can hear the fuel pump kick on and pressurize as normal .. but after trying to start it will run (whick i believe long enough to burn the fuel that was pumped at the first turn of the key to the on position) ..

could this be a fuel pressure regulator ? or does anyone know of any other sensor that tells the relay or pump to stay on ?

try running a jumper wire from the battery to the pumps in the rear, but remove the relay first. that is what I did to test the system on my 89 560SEL bypass the relay alltogether, if the engine will run that way, then either you got another bad relay or a bad ground in the system.

thanks ill give it a shot .. seems when i bypassed and car runs it sure sucks allot more gas than normal .. maybe the regulator is bad too .. also does anyone know what the "switch" is called that is mounted in the side of the throttle body ? its on the actually throttle body and is closest to you when you open the hood and look straight in ... i noticed that when i dont jump the wires the car will start and that thing kinda makes a loud click then the car shuts off .. if i jump the wires then it stays running and no click but im not sure if thats the actual problem and not something in the wiring before the switch .. maybe something that activates/deactivates it ..