They wiring is not designed like that. There is a system that senses the oil pressure and will give the fuel pump power but its a back up system.

When you start your car the PCM will turn on your fuel pump through a fuel pump relay. If the relay failed the car would just shut off. That could be dangerous. The back up system ran current through the oil pressure switch so if the relay failed while the engine was running then the fuel pump would get power until you shut the car off but it would not restart until the relay was replaced.

 

You’re right, the cars still acting up. Just restarts and dies when warm, unless you hold the throttle for a min then she’s good to go. Crank sensor? Coolant?

 

Fuel pressure? any new codes, Crank sensor failure without any code would a very rare issue.

When the car will not start its is missing spark or fuel. Step one is figuring out what is missing.

 

Thanks for saving me the headache, I got the codes read and there IS a new one- P0172: Bank 1 System Too Rich (INTERMITTENT). The other 4 codes read:
P0300: MULTIPLE MISFIRE (INTERMITTENT)
P0463: FUEL LEVEL SENSOR A CIRCUIT HIGH INPUT (HISTORY) (Fuel gauge is busted, usually reads high?)
P1516: THROTTLE ACTUATOR CONTROL/MODULE THROTTLE ACTUATOR PERFORMANCE (HISTORY)
P1516: THROTTLE ACTUATOR CONTROL/MODULE THROTTLE ACTUATOR PERFORMANCE (CONFIRMED)

The car hasn't jumped into limp mode and started misfiring since I replaced the throttle body, it drives fine really. Yes, there's a small maybe one second delay when you PUNCH the gas before the car responds, but maybe I'm just not used to drive by wire. The car fires right back up after you shut it off, but leave it for 5-10 minutes and she'll fire up and stall out. Flash CHECK GAUGES. This time CHECK GAUGES stayed lit for a few seconds while I held the throttle and kicked her into reverse, then went off after a few seconds when I started moving in drive. I need to verify fuel pressure and go from there, I think. Gotta pick up a gauge. As always, thanks guys

 

Been testing pressure today, Priming the key once gives you 10 PSI, seven cycles yields 40 PSI. The car starts up fine cold and keeps 40 PSI, but when shut off at operating temp the gauge slowly crept down to 20. Car fired back up, acted like she was gonna stall but kept going, gauge slowly built back up to 40 PSI. Shut off, tried to turn right back on and died, though gauge barely moved. Fired up and ran, built back up to 40. Dying pump?? Fun fun fun

 

Sure sounds like.

 

pump or fuel pressure regulator. have you changed the fuel filter (might be plugged) and had a look at whats in it.