what does the code p0401 mean. i get it about twice a month

 

DTC P0401
Exhaust Gas Recirculation (EGR) Flow Insufficient

The engine control module (ECM) tests the exhaust gas recirculation (EGR) flow when the EGR is in operation. EGR desired flow is compared to EGR actual flow. If EGR flow is lower than expected DTC P0401 will set.

Inspect the exhaust system for leaks, restrictions, or for modification of the original equipment manufacture (OEM) part.

Visually inspect for leaks between the MAF sensor and the turbocharger.

Visually inspect for a restriction in the air cleaner or the air intake ducts.

Visually inspect for a restriction in the turbocharger charge air cooler

Visually inspect for a restriction in the intake manifold.

Engine running, observe the DTC information with a scan tool. DTC P0401 should not set.

Sounds like your not flowing enough air compared to how much the EGR wants , or something aftermarket is causing false readings

Spray the EGR with soap and water and expect for leaks , if found replace the EGR Gasket

If you did all the above and still have the code ..If the actual EGR Code remains stationary or comes back after clearing it out , replace the EGR valve.

 

Hey man dont sweat the p0401.. I got it quite often once I cut my stock muffler off, and every time I stomped on it, i would get it.. It just means your truck is breathing like it should.. If you have an aftermarket exhaust.. it will throw that code as well.. U can get a finger stick to block it and several of the programmers block it..like the PPE..

 

the p0401 is an egr code, people often get them as soon as they tinker with their exhaust. Nothing to worry about. If you have a PPE tuner I think u can just make that code go away forever. I know for a fact u can with efi live.

You can look into getting a finger stick with an egr blocking plate. You kinda have to get both to make things good.

Heres a FAQ about the Finger stick and Blocker plate.

 

Thanks for the help guys all i have is the Technical Information when it comes to PSD and DMD

 

i have FSM's for LB7 dmaxes, and complete for 01 trucks. the lly's and lbz's have a little different problems but im familiar with them.

 

Thanks for all the help. Where can i pick up the finger stick and the blocking plate.

 

Ask the vendors they should be able to help you. Create a new thread in the price quote forum and ask for one. some people should have them.

 

FNG here. Member of another DMAX site. The code is thrown due to lack of back pressure from a modified exhaust. Easy fix would be like others have mentioned with blocker plate, and finger stick. Or what ever programmer you are using might have an option of disabling the egr. Still would have run a blocker plate.

 

quick question ive been getting a code that says #7 injector circuit should i start looking for a short or take it in it cut outs like the injectors gone but it fine as as soon as i clear it with my edge