So they both are rated for around the same pressure and flow.. is there an in-line regulator on the 2.5s? Seems weird if dodge to do that.. scanning through the manual now for answers.

although the 2.5 requires 49psi

 

95 MPFI V-8 should be wanting around 39-40 PSI. Pressure regulator is part of the pump module. Yours obviously isn't working.

 

RockAuto shows the 2.5 being a return style, like you have, with a regulator at the engine. The 3.9/5.2 is a non-return, regulator in the pump.

See https://www.rockauto.com/en/catalog/...assembly,10147 .

And where are you getting 49PSI? Page 14-8 in the FSM states 14.5PSI for a 2.5, and 35-45 PSI on the 3.9/5.2 for a 1995.

But yes, that's the wrong fuel pump. Might want to try the right pump instead.

For what NAPA charged for the wrong one, you could buy a new Bosch (OEM) pump from RockAuto ...

RwP

 

New pump no problem. Now to fix the rich condition. Thank you all for your help!

 

section 14 page 4 but that was at the injectors. I don’t have a return style like the 2.5s.

 

14-4 doesn't mention any pressures on the 1995 FSM (downloaded from the FAQ here). That's on page 14-6 for the 3.9/5.2, and 14-8 for the 2.5 .

The 1996 FSM shows 49.2 +- 5 PSI for all three motors for 1996.

And that was my point; the fuel pump they sold you was a 2.5 pump; regulates down to 14.5 at the throttle body for a 1995 2.5.

The 3.9/5.2 uses an integral regulator and no return line.

So now that THAT'S fixed - do your injectors now cycle?

And, BTW, you won't see the approx. 12V both sides of the injectors if they're commanded OPEN - the ECU side will be closer to 0V as it completes the circuit.

RwP

 

This was the page under testing fuel pressure.
I miss understood what you were saying.

injectors are operating correctly now.

I still have a lot to learn but this truck has been a lot of fun.


And this one

 

Wait.

Is your truck a 1995 as you stated, or a 1996 as you're quoting the FSM for?

RwP

 

That clears up a lot of confusion... I have it on a pdf from a file share site...

the file is miss labeled... awesome.

*FACEPALM*

 

There IS a proper copy of the PDF linked to from the FAQ here ...

RwP