02 Ranger 4x4 4.0L SOHC, p0402 error I have checked EGR and Solenoid and both are functioning correctly. I pulled the PDFE sensor last night and the hose from the exhaust is covered in carbon. It doesn't match up with what I have seen in other posts, 3 vacume hoses and only 2 wires running to it.
Is anyone familiar with this style (I'm pretty sure it's the right part!). I'm thinking I should pick up a sensor and replace the hose. The other thing that pops up when pulling the codes is the "Short Term Fuel" is reading 92.5% even with the truck off no codes just noticed the value. Anyone have any other recommendations?

Thanks,

Rob

 

The DPFE does not have vacuum hoses. It has two hoses running from the exhaust EGR tube to the sensor. I believe the electrical connector has three wires. If you see 3 hoses going to it, then you are looking at the wrong sensor.

Also verify the EGR valve itself isn't stuck open.. P0402 i believe is for "EXCESSIVE EGR FLOW" and while I would imagine a DPFE could cause that, usually when they go bad it sets a P0401 "Insufficient EGR flow". If you have a lot of carbon at the DPFE hoses, there's likely a lot of carbon build up on the EGR valve itself as well.

As far as 92.5 for short term trim reading... it just isn't possible. Are you sure you're not looking at the ENGINE LOAD value? You may have some scanner incompatibility issues, in which case i'd be questioning the code you pull as well.

What scanner are you using?

 

It was the wrong sensor I was looking at, I found the DPFE, it's tube mounted and comes off the pipe running up to the EGR valve. I haven't been able to test it yet, I also haven't been able to get it removed from the 2 hoses that connect it to the pipe!
The scanner was an Auto Tap (a friends), it didn't give any Ford codes either so I'm questioning exactly what I was seeing other than a P0402. I have a scanner on order so hopefully will get it next week and will dig a little deeper. I also have a "fuel cap" light on and want to see what that is about, I had it replaced when the truck was only a year old but want to see what the codes are.

Thanks for the reply,
Rob