Hello everyone. names klash, i got a 2001 ford ranger XLT its had the transmission replaced.


well its come to my attention given the fact this is my only vehicle i better start taking really good care of it. its got 265,000 miles on it.


Heres whats up -

the service engine lights been on for about 6-7 months and i just never cared to get it checked out. its been like that since i got it. which was 6-7 months ago.


i recently stopped at a autoparts place and got the codes checked it looks like its reading 2 different ones ,

P1120: throttle postion sensor out of range low


second code is

P1405: DPFE Upstream hose off

this truck was passed down to me and has been in my family since it was new. id really like to take care of it and fix it myself. i have no idea what im doing, where to start or where to locate these problems and fix them,


on the code reading P1405: DPFE Upstream hose off

i have a GENERAL , very small limited idea of what it is from reading. basically its some hose somewhere that could be clogged, dry weather rotted and cracked, bad seal,

and from what i understand theres some kind of computer sensor thing. it could be garbage just worn out, probably needs replacing.


the other code i havent even started to research so i have no idea.


if anyone has any helpful pictures, information or links to threads that would be of some use to identify what the cause of this is where it is located and how to fix it id be very appreciative.

thanks guys! glad to be here and i hope to keep this truck running for along time.

 

Welcome to the forum

Always good to include year and engine when you start a thread, also manual or automatic, and 2WD or 4x4

You posted the Trouble Code definitions Thank You and thumbs up, many think we should just know them all or look them up ourselves

DPFE is Differential Pressure FEedback, it is used by the computer(PCM) to tell how much exhaust gas is flowing into the intake thru the EGR(exhaust gas recirculation) Valve

DPFE sensor will have 3 wires and two hoses
Hoses run to EGR Valve's steel tube connected to exhaust manifold
One is closer to EGR valve than the other, sensor tells PCM the difference in pressure between the two hoses.
Since these are exhaust hoses they get water inside, also do crack
Sensor also gets water inside, that is usually what kills them

Don't know what engine you have so can't say where it is but this is what it should look like: http://bob-ayers.smugmug.com/photos/...25_acJom-L.jpg



P1120: throttle postion sensor out of range low
The TPS(throttle postion sensor) tells the PCM what the drivers Right Foot is doing, lol, gas pedal position, but it is located on the engine
Find the throttle cable where it connects to the upper engine, upper intake manifold
That is the throttle linkage
It opens the throttle plate which lets air into the engine.
On the opposite side of intake from the throttle linkage is the TPS, it is connected to the other end of the rod holding the throttle plate.
It also has 3 wires
5volt
Out to PCM
Ground

Works like a volume control or light dimmer
It gets 5volts
If your foot is off the gas pedal, the "Out to PCM" wire will have .69 to .99volts, under 1 volt
If you press gas pedal down to the floor then "Out to PCM" wire will have above 4.5volts
So voltage in between 1 volt and 4.5 volts is how PCM can tell what driver wants to do

You can use a volt meter to test these voltages, use a sewing pin to pierce the wires

But I would at least unplug it's 3 wire connector and check for corrosion, same for DPFE sensor.

Picture of TPS location on 4.0lsohc: http://easyautodiagnostics.com/image...11/image_2.jpg

You can see throttle cable(and cruise control cable) running over to opposite side of intake
Behind the TPS(on this engine) is the IAC(idle air control) Valve, remember what that looks like, they often need to be cleaned, easy to do 2 bolts and a little elbow grease, lol.

Just as a heads up, 90% of sensors replaced by DIYers were still good, simply unplugging them to install new sensor would have fixed old one, lol
But they can fail, DPFE sensor is more common failure because of the water inside.
TPS doesn't fail very often, so check those wires

 

He has a 3 litre, so location is here of course, but I think being a 2001, it will have the plastic upper intake manifold.
To the OP, if you have the metal DPFE sensor, then replace it with the solid state plastic one as shown in the screen shot. At 265K it's probably compromised in some way.
Someone may have already replaced it with the plastic one. If you have the plastic one, then leave it.

The water that Ron mentioned gets inside the sensor and internally corrodes the metal.
It eats away around the internal seals until the water and corrosive exhaust gasses gets to the circuit board.
The sensor doesn't last long after that happens.