Fuel pressure too high? Pressure Regulator? | Page 2 | Ford Explorer Forums - Serious Explorations

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Fuel pressure too high? Pressure Regulator?

If harbor freight gauge is showing 65 psi at idle, is my filter in need of change? Others online have reported 65 psi as well at idle. It took about an hour last night to drop to 40 psi.

That's a great pressure, anything under 60psi is a worry with a 99+ Ford. Change the filter, if it's not known how old it is, it's time.

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65 PSI of fuel pressure is about as good as it gets. That's not your problem.

So why negative trim on long term?
So no way my filter needs changing if I have good psi pressure?
I don't know what previous owner has had done.
No real issues, just seeing -9 and -9 at idle on ltft.

Fuel rail 65 at idle
O2 b2s2 0.815
O2b2s1 0.090 volts
O2b1s2 0.045
O2b1s1. 0.820

Stft b1 1.6
Ltft b1 -11.7
Stft b2 0
Ltft b2 -9.4
@ idle , my negative ltft drop as rpm goes up like one is -6 @ higher rpms

Pcv valve would rattle sometimes when I shake it. AUTOZONE 5.50, FORD WANTS 25.00

Pcv valve would rattle sometimes when I shake it. AUTOZONE 5.50, FORD WANTS 25.00

The PCV should rattle every time you shake it.

Pcv valve would rattle sometimes when I shake it. AUTOZONE 5.50, FORD WANTS 25.00

Does the 2003 ST still have the PCV valve twist-in on the rear of the DS valve cover? Does it also still have the coolant line as part of the PCV valve? If the '03 still uses this weird PCV valve I don't see how AZ sells it for $5.50. I think I paid around $11.xx for mine at Advance. RockAuto currently shows the Motorcraft for $9.58 (plus shipping).


Note: RockAuto shows 3 different style PCV valves for the '03 ST.

Mine is not heated but is on back of engine drivers side and turn counter clock wise to remove

Question - If you stick a finger inside your exhaust tip does it come out black and sooty? If it does I'd be thinking upstream O2 sensors. If you've said you've replaced them already I may have missed it. Heated O2 sensors are designed to last around 120,000 miles and in my experience do not always throw codes when they are no longer working correctly. This will effect your fuel trims and fuel economy.

The downstream O2 sensors just monitor the cat efficiency and have no effect on how the engine runs.

Negative ltft, my stp air filter has less than 9000 miles, and I don't live on or normally drive a dirt road.



Changed air filter, pcv, at first it appeared it dropped w numbers (example neg 10 went to negative 8)..I drove 30 miles one way and back and the numbers are almost identical. 8 don't know if it takes awhile for ltft to calculate.

65 or 64 psi on fuel rail dropped to 60 pretty quick after turning off and was 35 psi about 2 hours later.
Tried spraying carb cleaner this morning for leak didn't notice anything.
Code p2195 set check engine light