2001 b4000 check engine light

[LuigiS]

Hello all...

Hate these lights! I am getting a p401 code. I have checked everything, EGR valve, etc, etc and all are up to spec. but the damn light keeps on coming back after resetting. The engine only has 33,000 km and is otherwise working well. Has anyone any ideas? short of changing everything, I am stumped....

-Gino

[Kyrasis6]

Code P0401 is an EGR flow error, the computer is checking for egr flow and its not getting any. If the EGR valve checked good you'll probably have to take it off, clean inside of it and run a metal pipe cleaner through the EGR passageway to clean the gunk out. Clear the code and I bet it won't come back.

Just curious are you taking the truck to a shop to read the codes or is there some sort of diagnostic mode that can be engauged? The factory manual doesn't say if it has one.

[LuigiS]

Thanks... Have done all that and the valve proper is good and holds a vacum - so no leak there. I am going to change the solenoid as perhaps that is causing a lack of flow to the valve..

In terms of the codes, I have a reader and just cross reference the code to the reference book. Not very expensive and less of a hassle than going to the shop...

-Gino

[griffse]

Hey Luigis,
My 2001 B4000 had the same problem, and the dealer told me it needed like $380 worth of parts and replacement labor to correct. I took it to a friend who is a shadetree type and he found a ruptured rubber elbow near the airfilter that wraps around the back of the engine near the top. Replacing that part, $38, fixed everything. FYI the DFPE sensor on several of these trucks was recalled and will be replaced for free by a dealer.

[LuigiS]

Thanks!

I just found out about the recall - which is all that is was. Took the dealer less than 5 minutes to fix. What ticked me off though is that was one of the first things I checked and they told me there wasn't a recall and that it was going to cost me $100 to diagnos the fix. I checked directly with Mazda who told me about the fix and the dealer still wanted to charge me. Go figure! At any rate, it is all fixed. Thanks for the reply and the fix. I will keep it on hand for the next time!

[griffse]

No Problem, what irritated me was that there was no notice of this recall for people outside of the Mazda dealerships.