Easier way to check fuel pressure - Page 2 - Toyota 4Runner Forum

Masonchamby · 05-20-2022, 10:36 AM

Thank you for the post!

19963.4lsr5 · 05-20-2022, 06:27 PM

They also make a banjo bolt replacement with an 1/8” NTP thread in the head also. Which measures the fuel rail pressure after the regulator.

Sent from my iPhone using Tapatalk

DJRodriguez88 · 12-14-2023, 05:54 PM

What's the difference in measuring fuel pressure before or after the regulator?

I thought before the regulator would be constant and after the regulator would fluctuate with rpm/load

Bad Luck · 12-15-2023, 06:18 PM

Quote:

Originally Posted by DJRodriguez88

What's the difference in measuring fuel pressure before or after the regulator?

I thought before the regulator would be constant and after the regulator would fluctuate with rpm/load

Regulator is vacuum dependent and therefore load dependent so before the regulator it should be fairly stable, but increase with engine load (and as engine vacuum decreases). I'm not sure if there's even a spec for post regulator measurements as that fuel is returned to the fuel tank.

Js'00imited4runner · 04-03-2024, 07:46 PM

Quote:

Originally Posted by DJRodriguez88

What's the difference in measuring fuel pressure before or after the regulator?

I thought before the regulator would be constant and after the regulator would fluctuate with rpm/load

I'm not completely sure about your question..I was just putting this out there because their hadn't been any alternatives to checking fuel pressure besides the specialized union bolt for the fuel rail. I ended up dropping the tank and putting in a new fuel pump and it solved my issue with the lack of fuel. It read constant during idle and under very slow throttle input but as soon as I gave it anymore it would drop to like 10-15 psi.

DJRodriguez88 · 04-04-2024, 10:57 PM

Quote:

Originally Posted by Js'00imited4runner

I was just putting this out there because their hadn't been any alternatives to checking fuel pressure besides the specialized union bolt for the fuel rail.

I ended up doing your mod. Works great thanks! 👍

Site Navigation