Help, I'm being plagued by a recurring 401 code. I have a 97 F150 4X4, 4.6 L, automatic. I have changed the EGR valve, ECT sensor, Vacuum Regulator, and DPFE sensor. I reset the ODBC and 50 miles later it triggers another 401. If I drive only highway miles, it will take about 100+ miles for it to trip the code, so stop and go is definitely more conducive to creating the error. I am in a bind with this problem, I cant pass emissions test to get my new registration. , When you reset the ODBC codes in the computer, you have to drive it for 200+ miles before you can get it inspected again.
Help,,,,,,, how do I get rid of this demon 401 code???????

Short of putting the truck up on jacks and putting 200 miles on it in my backyard,I'm running out of ideas and luck with the law,, Atlanta is strict and most of these cops have no idea of what you are talking about when you mention ODB-II codes and EGR problems...
thanks ron...

 

Did you clean the EGR ports? Did you test the EGR valve?

Click on SEARCH and enter "P0401" for many previous threads with advice and pictures.

Steve

 

You did (unfortunately) what most people do when the get a DTC code. You threw parts at it and it didn't solve your problem! A DTC code is there for a place to start your diagnosis as to what combination of events caused the code NOT what sensor to replace!

As mentioned above do a search on p0401. The 4.6 is FAMOUS for clogged EGR ports. The EGR valve itself almost never goes bad. Clean the entire EGR system then re-set the PCM and all should be well.

Good luck-

 

Thanks for the advice,, I have bought a 5 gal bucket of cleaning solvent and will submerse the throttle body in it..I took it off last night and it was definitely dirty and gummed up..thanks again,, will let you know how this works,,ron.

 

Ok, took off the throttle body and it was in great condition,, didnt need cleaning..Then took off the 90 degree elbow between the throttle body and the intake.. Boy was this thing plugged big time.. there were things growing out of the two EGR ports that looked like an science experiment gone bad.. cleaned them out with a wire rifle cleaning brush and reassembled everything. Smokes the tires now,, well on a wet street with a little brake pedal..... yeah!! no more "check engine" light...thanks