1G New fuel pump but after sitting overnight is still hard to start

[Beast-Mode DSM]

I replaced my fuel pump but even still after sitting for a few hours or so when I get in and try starting the car it is hard to start.

 

[luv2rallye]

Check to make sure fuel pressure is maintained in the rail (for days). A leaky FPR often is the problem.

 

[Beast-Mode DSM]

Will a fuel pressure regulator from a turbo model work?

 

[luv2rallye]

Depends on your year, model, engine (and from/to) but probably not.

 

[Beast-Mode DSM]

1994 eagle talon 463 non turbo

4g63

 

[Mech Addict]

Did you verify the coolant temp sensor is working? You should be able to check the resistance when cold and compare to spec., which is 2,450 ohm at 68F. It goes down when warm (295 ohm @178F) and the ecu will substantially alter the amount of fuel while starting based on the cts resistance. They’re generally not expensive (as in $10) so if you could simply put in a new one and see. Generally not the best method, but I have done this style of “diagnosis by replacement” on occasion, especially with electrical.

 

[1990TSIAWDTALON]

I would "assume" a turbo FPR would work, it just never would see positive pressure. If you had one laying around, I would put it on as a test.
Change the CTS..........or at least confirm it is working and getting a signal to the ECU!

 

[97egl]

I would "assume" a turbo FPR would work, it just never would see positive pressure. If you had one laying around, I would put it on as a test.
Change the CTS..........or at least confirm it is working and getting a signal to the ECU!

They are different. The FSM calls for 47 psi for N/A engines. 43 psi for turbo Auto and 37 psi for Turbo manual. The pressure is tested at idle with the vacuum hose off so they would have to have different springs internally to make different pressures.

 

[1990TSIAWDTALON]

It was only a test not a fix. OPs car was getting fuel in the video but not sure if it was holding pressure on the rail.
I know it was suggested to pinch the return line closed (to create pressure in the rail) but I never saw if it was tried or not.

 

[steve]

Base fuel pressure is different between the various flavors of 1G with the NT being the highest.
Remember the ECU is programmed for a injector flow rate and changing the FPR will change the effective flow rate.

 

[1990TSIAWDTALON]

Yes but it was just a suggestion for a test.
I sure appreciate the knowledge base on this. It is good for the forum! You helpful guys rock it!