CODE 401 for ever
 

Hello all, I have 1995 2.3 ranger and i have a CEL light on for about a year. got it read and code 401came up. they wanted to charge me 900.00 dollars to do all this that i have already done. Replaced egr and its sensor, cleaned egr tube with carb cleaner, ran seafoam, replaced hoses to sensor and nothing. Code keeps coming up. I have cleared the code by unplugging negative cable for hours. what can it be? I plan on removing upper intake and cleaning carbon buildup at port where it attaches to egr valve. but hesistant because of throttle cable. What do u all think?

i would say it is the DPFE (differential feedback pressure egr) sensor

i have already replaced dpfe sensor. Should i return it to auto zone and get another? Someone told me it may be the o2 sensor or cat converter, but i told them code did not pop up for that. what u think?

i dont think the o2 sensor would throw a code for EGR

IT IS THE DPFE. YOU HAVE TO USE THE MOTORCRAFT DPFE TO CLEAR THE CODE PEREMANTELY!!!

My dad's F150 originally had the aluminum DPFE sensor when it failed, and replacement was plastic. I went through about 6 different plastic DPFE sensors, from AZ to OEM, and they all failed within a few weeks or months. I finally went to a salvage and bought a USED aluminum sensor...and the code never returned.

fixed code 401
 

Just to let you guys know with the same 401 code. it was my upper intake that was clogged with carbon. had a friend remove intake and clean it with carb cleaner. stuff was hard like a rock. so for future 401 codes be advised insufficent flow means it clogged and you have to remove the carbon buildup in the upper intake before you replace all that stuff that i did before. I passed emissions and did not have to pay precision tune the nine hundred dollars thay qouted me. yeeepeeeee!!!!

Thanks for posting back your fix!

*A lot of people don't take the time