Fuel Pressure Question/Check

[94pony]

Fuel Pressure Question/Check
Okay I am pulling codes 181 and 189

181: Heated Exhaust gas Oxygen sensor - Voltage signal not switching: Indicates lean during part throtle engine operation (BANK #1)

189: Heated Exhaust gas Oxygen sensor - Voltage signal not switching: Indicates lean during part throtle engine operation (BANK #2)

While at idle my fuel pressure is at 35 psi, and moving a little with the lope from my b-cam. Is 35 psi okay? Any idea or methods to check the fuel system?

 

[KENS89LX]

The fuel pressure should be around 38-39 with the vacuum hose disconnected off the fuel regulator, if you have an adjustable one, 35 would be a little lean.

 

[HISSIN50]

Have you checked your O2 signal output?

 

[94pony]

The fuel pressure should be around 38-39 with the vacuum hose disconnected off the fuel regulator, if you have an adjustable one, 35 would be a little lean.

Mine sits right at about 40psi with the hose disconnected.
Let me ask you this with the hose connected and reeving up the motor to like 2500-3000rpm my fuel pressure sits around 35 psi. Is this right I thought it would go up?

 

[94pony]

Have you checked your O2 signal output?

Do I still need to do this considering I replaced them yesterday?

 

[HISSIN50]

Mine sits right at about 40psi with the hose disconnected.
Let me ask you this with the hose connected and reeving up the motor to like 2500-3000rpm my fuel pressure sits around 35 psi. Is this right I thought it would go up?

It would depend upon the rate of change (accelerating vs holding it at 3K RPM), as well as load (if watching it while driving). If you are idling and snap the throttle open and let go, it should spike up and then fall back to your idle reading (the FPR works off the vacuum signal. You have lots of vac at idle, a good bit at cruise and almost none at WOT).

Do I still need to do this considering I replaced them yesterday?

Just because a code is thrown doesnt mean the sensor(s) is/are at fault. Look for damaged wiring or a blown HEGO fuse. This is why it's nice to check the actual signal with a DMM so you can see what the sensor is doing. Do NOT puncture the wire sheath to the O2's however.