Your signature says 2001 with 3.0l?
So 2001 with 4.0l??
15-18mpg for 4.0l SOHC would be about right, but alot depends on the tires, if it is lifted at all or a 4x4, and of course the gas pedal use, lol.
Here is a code list for Ford:
Ford OBD-II Trouble Codes
P1407 EGR No Flow Detected
P1408 EGR Flow out of Self-Test Range
P1409? EGR Vacuum Regulator circuit malfunction
P1409? Electronic Vacuum Regulator Control circuit fault
P1410 EGR Barometric Pressure Sensor VREF Voltage
And a generic list:
OBD-II Check Engine Light Trouble Codes
P0400 Exhaust Gas Recirculation Flow Malfunction
P0401 Exhaust Gas Recirculation Flow Insufficient Detected
P0402 Exhaust Gas Recirculation Flow Excessive Detected
P0403 Exhaust Gas Recirculation Circuit Malfunction
P0404 Exhaust Gas Recirculation Circuit Range/Performance
P0405 Exhaust Gas Recirculation Sensor A Circuit Low
P0406 Exhaust Gas Recirculation Sensor A Circuit High
P0407 Exhaust Gas Recirculation Sensor B Circuit Low
P0408 Exhaust Gas Recirculation Sensor B Circuit High
P0409 Exhaust Gas Recirculation Sensor "A" Circuit
Yes, EGR issue can bring MPG down, but you could spend hundreds of dollars on parts and still not fix it, you need to get the code or codes to get an idea of why CEL is on.
Auto parts stores read the codes for free.
DPFE sensor is a common problem but not the only problem.
A fuel leak can drop MPG, park some place clean a dry, covered Mall parking is good, go have lunch, and check carefully for drops on ground or smell of fuel.
Filler tube and vent tube are common places for leaks.
And a 2001 will be using 65psi fuel system, so a small leak will leak alot of fuel.
Does the engine idle go high when cold started, 1,000rpms?
And then when warmed up does it idle at 750rpm?
If you have a higher idle when warm that could mean another issue.
Computer controlled engines(all of them) have two modes of operation, Open Loop and Closed Loop, RPM at idle can indicate which mode computer is in.
Open Loop is also Choke mode, for cold engine operation, computer ignores O2 sensors and runs engine rich with high idle until it warms up.
Closed Loop means engine is warmed up and computer is using O2 sensors to trim the fuel, idle would be 650-750rpm, depending on transmission.
Closed loop gets best fuel economy.
Does your temp gauge run at just below 1/2?
Or does it stay lower?
Is heater blowing very hot or just luke warm?
If engine isn't warming up all the way you could be stuck in Open Loop, engine runs great in open loop, extra power because of extra fuel, but MPG sucks, lol.