Hi,
I have is the check engine light and this code P0404 Exhaust Gas Recirculation "A" Circuit Range/Performance (google)

I replaced the EGR Valve but still get this code.

 

The oil pressure SWITCH on the engine needs to be changed, not an uncommon repair

The oil pressure switch is on drivers side of engine toward the rear of the engine/Head drawing here: http://repairguide.autozone.com/znet...3f8021b7e1.gif


The P0404 code can mean quite a few things about the EGR system, but my guess is that the EGR Valve needs to be cleaned

The 2.5l Lima engine is the same as the earlier 2.3l Lima engine

EGR Valve removal seen here: https://www.ranger-forums.com/engine...-engine-69816/

If the EGR valve gets dirty it won't close all the way so "excessive flow"

It can also be a DPFE sensor issue, but thats usually P0401 code, "insufficient flow", but not always

So there is no definitive "fix", like the oil pressure gauge, you will need to start doing some disassembly to investigate

 

Okay. I found the oil pressure sensor. I was thinking if I removed the EGR Valve I’d have some more room to work with.

 

I replaced the oil pressure sensor and it's working fine now. I replaced the EGR Valve and I still have the engine light and same code even after erasing the code.

 

Good stuff on the oil pressure gauge

First, you can't "clear" emissions codes, they will usually come right back after you clear or reset the computer, that's normal
This is to prevent people resetting computer to past Smog Tests
So after doing any repairs give it a day or two of driving to see if the code(s) clear

Have a look here at clearing emissions codes: Ford Motor Company Driving Cycle

How did the EGR valve look?
Was it clogged up?

First I would test if new EGR Valve is working OK
If possible put a longer vacuum hose on the EGR valve
Start engine
Then "suck" on that longer vacuum hose to open EGR valve
Engine should start to stumble as exhaust gases flow in
If that happens then EGR valve is working

If EGR valve works then you are down to 2 things
EGR Vacuum solenoid or DPFE sensor
Follow the EGR's vacuum hose to the EGR solenoid, it should have 2 hoses, the other hose should run to a vacuum hose connected to the intake manifold
Make sure hoses are not cracked
It will also have a 2 wire connector, unplug it and check it for corrosion and plug it back in

DPFE sensor has 2 hoses, one larger than the other because they need to be connected in correct order
Both hoses run to the EGR Valves TUBE, which also have an order, one larger than the other
DPFE also has a 3 wire connector, unplug it and check it then plug it back in

DPFE sensors can get water inside which cause them to fail, its from the exhaust system, so DPFE sensors often fail every 3 to 5 years because of this

 

I replaced the DPFE sensor and my check engine light isn't showing anymore. I have encountered another problem recently when I went to 2 stores. I left one and had a hard time getting it to crank and then the same thing happened to me at the other store. Now this probably took me a 20 minute drive to get there. It drives fine and everything on the way and back home. When I got back home I left the truck rest and when I went to see if it would do it again it didn't. Cranked right up as it normally does.

I'm wondering what could have caused that issue? My brother said it could be the purge valve?

 

Can be, but it wouldn't ever prevent engine from starting at all, just slow to start, stuck Purge valve is like a Vacuum leak, so engine would also idle at high RPM and idle rough, also can set Lean Code, and purge valve code

Engine not starting first crank be so many things thats it better to wait a see if it repeats, and then repeats several times

 

oh it starts but it’s slow to start. Sorry about that.
it does feel like it idled high because when I crank it up and put it in drive or reverse it will want to pull itself without me putting my foot on the gas. I wanna say it idles rough or something at the start like it’s about to die on me but never does. No codes have shown up yet after driving it 2-3 days after fixing the other sensor.