Hell first post on this forum thought I try what you guys suggest so here it goes.

I own a 1998 Ford Ranger XLT 2.5L 2WD
Now about 2 years ago when I bought it was fine then a couple months after I brought it to my base in Nevada I got the dreaded P1401 code.

So I did everything everyone suggest so far with out fixing it and I have no darn clue whats wrong with it.

So I replaced both O2 sensors, completely replaced the exhaust all the way back, put a full flow custom air intake in, replaced the airflow chip, replaced the EGR valve, Replaced the EGR Sensor(DPFE, same thing right?). The only thing I have yet to replace is the actual tubes coming into the sensor. I am completely stumped and I really dont wanna bring it to the dealer to have them tell me what I already know for 40-60 dollars.

Any idea's on this one would be greatly appreciated.

 

Welcome to FTE!

I'm not an expert on this issue, but here's some light reading on the subject:

EGR problem - Very detailed thread with specific diagnostic tests to perform
EGR High input/ P1401
1998 Ranger with obc P1401 code

-Jim

 

Here's few more excellent resources regarding DPFE System Operation & Testing:

http://www.tomco-inc.com/Tech_Tips/ttt35.pdf

http://www.tomco-inc.com/Tech_Tips/ttt36.pdf

 

have you tried disconecting the negative side of battery for a few minutes? my ford probe gt i had back in the day, i had a light come on, fixed what needed to be fixed but the light didnt go off, i disconnected the battery and it didnt come back on after that.

 

Yes sir I sure did.

Looks like I will have to break out a multi meter tonight and check the voltages and resistances listed. Good thing I am a electrician :P anyways more input is always liked :P, I will post my results.

 

Could the air pump be the culprit?

 

I too live in NV and have a '98 2.5l which recently started throwing the check engine light for the p1401 code. I disconnected the battery and the code went away but came back a couple days later. After reading about what a pita this code is to get rid of I am a bit reluctant to just start replacing parts in hopes of curing the problem...I did enough of that with my old Mustang!

My truck has also pinged badly after being warmed up for 15-20 minutes ever since I bought it in 6/09....Ive tried every grade of gas (even 100 from Rebel just to see if it would help, which it did as in let me drive the truck a bit more before the pinging started). I made a couple threads on here about it and got plenty of responses but nothing I have tried has cured it. I replaced spark plugs, wires, cleaned and then replaced MAF, seafoam, techron concentrate, taken off the EGR and completely cleaned it and the line to the exhaust manifold. Both upstream and downstream o2's are new and fuel filter has been replaced.

First I am going to replace both the hoses from the EGR line to the DPFE, where and what would be the best size and kind of hose to use. Im assuming it has to be high temp hose since it has hot exhaust gas running through it. I have also noticed that there is some wierd kind of silicone/rubber on the DPFE connector....the previous owner used silicone crap everywhere on this truck for some odd reason although I have owned the truck for 9 months before the the 1401 code came on. BTW the truck only has 135k miles on it now but had 127k on it when I bought it and still pinged like all hell. I am so frustrated, especially since summer time is coming and with 120 degree temps its going to ping much worse and I would rather fix the problem before I burn up a piston or something.