I keep getting the P0401 code on my 2001 3.0l Montero Sport. Vehicle starts, idles, & runs great. I checked the EGR + ports all clean, EGR appears to be working. Retrieved following Freeze Frame (I don't know how to interpret)

Fuel Sys 1 OL-Drive
Fuel Sys 2 OL-Drive
Calc Load (%) 13.73
ECT(F) 203
STFT B1(%) 0.00
LTFT B1(%) 3.13
STFT B2(%) 0.00
LTFT B2(%) 5.47
Eng RPM 1503
Veh Speed(mph) 49

Any suggestions on narrowing down the culprit?

 

What was the solution to this problem?

 

I have

 

I have the same problem... ERG valve & Solenoid replaced

 

Most likely bad EGR solenoid. You can check to make sure EGR valve is working by running engine at idle, and pulling vacuum with the hand pump on the ERG valve vacuum port. If engine sputters and dies - EGR valve is working properly.

 

Yes and yes... all of that has been done...still showing the code

 

Did you replace EGR solenoid with Mitsubishi OEM, or with an aftermarket? I found that aftermarket ones work at first, but eventually throw the code again. It had something to do with the duty cycle of the solenoid. It is not just a simple ON/OFF state. These solenoid cycles hundreds of times per minute to regulate EGR amount admitted to the engine. Aftermarket senoids somehow fail with that load.