New OEM fuel pump assembly...45 psi system pressure?

Just installed a brand new OEM fuel pump assembly after the original unit failed at 197k. The truck fired right up, but I’m seeing a steady 45 psi fuel pressure when tested using a T-fitting on the return line, per the service manual procedure. The manual specifies a pressure range of 40.8 to 41.7 psi, so technically I’m a few psi over spec.

That said, both short-term and long-term fuel trims on both banks look excellent—LTFT is under 2%, and STFT fluctuates between 0% and 2%, which suggests the ECU is compensating just fine. I fully warmed up the truck and cycled it on and off a few times over several hours, but the pressure consistently holds at 45 psi.

I'm wondering if the slightly elevated pressure could be due to the new pump being fresh or possibly a result of the ECU still re-learning fuel trims after battery disconnect. Just looking for some insight or confirmation—technically it’s out of spec, but the trims and drivability seem spot on.

Thanks guys!

 

Well for starters you should be checking fuel pressure on the feed line not the return

But otherwise the fuel trims do reflect a healthy system

Maybe the gauge is slightly off

 

I'd want a little more, than a little less.

Also, the later generation with Dual-VVTi calls for 46-47 psi.
I bet they don't make a pump for early/late engines.
I bet they all get the "newer" pump.

And as stated, unless you have a good high end gauge, the PSI likely off a bit.
2 or 3 psi isn't a big deal for most diag work.

 

Thank you for the later VVTi specs, the pump is a new version for sure even though the part number is the same.