What is this? Found disconnected hose/tube.

[Lildon21]

Hey can someone tell me what the device in the top left of the photo is? I noticed the metal tube on bottom right had no hose on it and then saw the one next to it has a hose, but is not connected to anything. Looks like it goes into the module thing in the top left of photo.

It's a '96 Ford Explorer V6

Thanks!

 

[Turdle]

You are correct.
It's the dpfe sensor, which connects to the EGR pipe thru 2 hoses. Ref line runs to nipple closest to engine

 

[Lildon21]

You are correct.
It's the dpfe sensor, which connects to the EGR pipe thru 2 hoses. Ref line runs to nipple closest to engine

Thanks so much for the reply. Can you explain which one is the ref line? Is that the one that already has a hose on it (left)? And I guess I need to find another hose to connect the right port of the EGR pipe to the sensor nipple as well. I can also probably find the answer now that I know what it is haha. I'll check the repair manual.

Also is it bad that I have been driving with these two hoses disconnected? Not sure how long it's been like this.

Thanks again!

 

[Turdle]

Ref is printed on dpfe to indicate ref line,

REF

Driving with the check engine light on is bad.

 

[Lildon21]

Ref is printed on dpfe to indicate ref line,

REF

Driving with the check engine light on is bad.

I'll give it a look and figure it out.
Also, check engine light is not on. And yeah that's obvious. Thanks.

 

[Turdle]

You should have codes read. Hard to believe no code was set driving like that.

Does the check engine light turn on with key?

 

[Lildon21]

No it doesn't. I've actually suspected there might be a problem with the check engine light. Either the bulb or PCM. Instrument cluster is a pain to check the bulb...And I'm not entirely sure where the PCM connections are.

I'll get around to that though. Just replaced the radiator, water pump + fan clutch, and thermostat + housing today. And I think the new thermostat got stuck open...so that's fun.

 

[toypaseo]

Those are special hoses. One brand besides OEM, is Dorman.

 

[Lildon21]

Those are special hoses. One brand besides OEM, is Dorman.

I ordered these off rock auto:

Hopefully the sensor isn't bad too...

 

[wollimann]

These DPFE sensors have trouble all day long. Metal sensors get moisture in it, plastic sensors melt sometimes.

More Information for HELLA 009409391

EGR valves have problems too, get stuck sometimes...

EGR Backpressure Transducer: Description and Operation — 1996 Ford Explorer 4WD V6-245 4.0L Service Manual | Operation CHARM

Detailed repair manual for the 1996 Ford Explorer 4WD V6-245 4.0L.

charm.li

Hope that your Explorer will run better with both hoses attached in 2025.

 

[410Fortune]

Yes the early trucks had the aluminum bodied dpfe
Differential pressure feedback exhaust
Just fyi
The aluminum ones plug up internally with corrosion and crud
I always replace the metal ones with the 98-01 plastic style

Your check engine light bulb is likely just out
The cluster is not that hard to get to
You just need a Phillips, a 7mm and a 8mm socket
Can have the cluster out in less then 15 minutes once you do it a time or three hundred

If you installed the new thermostat with the weep hole pointed up then I really doubt it is stuck, the 4.0 has a hard time burping all the air from behind the thermostat sometimes. The temp will read higher because the sensor is actually in a pocket of trapped air. There are several clever methods members have come up with to remove the air bubble over the years… I have found a couple I like. When it’s at temp just start squeezing the upper hose, this helps the system move coolant and release the air.

Make sure the overflow tube is not plugged.

Some people park on a steep incline with the engine raised, I have also been known to pour hot water down the upper rad hose directly to the backside of the thermostat forcing it open and thus releasing the air

 

[Lildon21]

Yes the early trucks had the aluminum bodied dpfe
Differential pressure feedback exhaust
Just fyi
The aluminum ones plug up internally with corrosion and crud
I always replace the metal ones with the 98-01 plastic style

Your check engine light bulb is likely just out
The cluster is not that hard to get to
You just need a Phillips, a 7mm and a 8mm socket
Can have the cluster out in less then 15 minutes once you do it a time or three hundred

If you installed the new thermostat with the weep hole pointed up then I really doubt it is stuck, the 4.0 has a hard time burping all the air from behind the thermostat sometimes. The temp will read higher because the sensor is actually in a pocket of trapped air. There are several clever methods members have come up with to remove the air bubble over the years… I have found a couple I like. When it’s at temp just start squeezing the upper hose, this helps the system move coolant and release the air.

Make sure the overflow tube is not plugged.

Some people park on a steep incline with the engine raised, I have also been known to pour hot water down the upper rad hose directly to the backside of the thermostat forcing it open and thus releasing the air

Hey, thanks a bunch for replying. Very helpful post.

So I did install the new thermostat with the weep hole pointed up. Also I let it idle for quite awhile, added coolant periodically, and squeezed the upper hose to try and get all the air out. I noticed the temp gauge going back and forth after I got to highway speed and it drained the overflow reservoir. Then I added more.

After driving it for about 25 mins at highway speed (next day) the gauge is still all the way cold. It's around 32 degrees over night here fyi.

I thought I was being smart and bought the thermostat that has the clips to lock it open in case of failure. I think it locked itself open because of that. I'm gonna drain the coolant and take a look at the thermostat today, I have a spare one cause it came without the gasket so I ordered another.


Thanks for the info on the dpfe sensor, I'll just order a new one after reading your advice. I'm Still confused on which hose goes where, but from what I researched it looks like the two hoses/nipples are different sizes. So I think I can figure it out that way. I see the REF imprinted on the sensor, but that doesn't tell me which end to connect from the EGR tube (left or right).
Help on that would be cool if anyone knows. Otherwise I'll figure it out.

Thanks again for the replies.

 

[Turdle]

Don't like fail safe thermostats. I feel they lock open during heat soak-- shutting down hot engine. Coolant actually gets hotter when soaking like that.

 

[Lildon21]

Don't like fail safe thermostats. I feel they lock open during heat soak-- shutting down hot engine. Coolant actually gets hotter when soaking like that.

Yeah. I thought I was being smart. First time replacing the thermostat. And I did basically the entire cooling system besides the heater core. Cause I discovered I had to basically disassemble the entire car to do that.

This is the one I got, and I don't recommend....

 

[Lildon21]

Gonna take the gasket from that thermostat and put it on the OEM one I got from rockauto (non Fail-Safe). Hopefully that will do the trick.

Fumny this post was about the dpfe sensor and now I'm talking about the cooling system. Haha, sorry about that.

Thanks for all the help. Will take any more advice if it's out there. Otherwise I think we're good here.

 

[Turdle]

While the cluster is out, 194 LEDs in place of bulbs.

LEDs must have correct polarity though, and be dimmable.

Went off topic also, kinda.

 

[Lildon21]

While the cluster is out, 194 LEDs in place of bulbs.

LEDs must have correct polarity though, and be dimmable.

Went off topic also, kinda.

Awesome, thanks for that! I'll just replace them all with LEDs while I'm in there

 

[410Fortune]

Get good leds not the cheapest ones read the reviews

The sizes of the two egr hoses are different so it is pretty obvious how they route
One small one large

I’ve had trouble w those thermos before also
Silly design imo

Battle on

 

[BTR]

Can you please clarify? When you say, “install the thermostat with the weep hole pointed up,” I’m no sure what that means. Are you saying install the thermostat oriented as shown in post #14… or install it flipped 180-degrees from how it’s shown in post #14? Please advise. Many thanks.

 

[410Fortune]

Some Thermostats have a small weep hole in them, it simply gets installed at the 12 o clock position. It’s purpose is to allow trapped air to get out so it must be at the top

The spring on a thermostat always points towards the engine

Weep Hole circled in red
Easy to overthink stuff