P0401

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mazda5 GT 2009
P0401 and P2177

My 2009 5 GT with 117K+ miles just indicated Cel P0401 EGR flow insufficient. Is this likely a simple replacement job? I usually buy the part online and go to my mechanic to have it installed. Whatbrands are good to use or is it important to use OEM for this one? Thanks
 
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I ended having to replace the EGR valve as recommended by mechanic. Code was cleared. Car runs fine except after about 150 miles I now have a new CEL P2177. Could this be related or is this a new issue?
 
I ended having to replace the EGR valve as recommended by mechanic. Code was cleared. Car runs fine except after about 150 miles I now have a new CEL P2177. Could this be related or is this a new issue?

System Too Lean Off Idle Bank 1 is what your code is now. You could easily have had multiple issues but unrelated.
Try this first, buy a can of MAF cleaner, and clean your MAF before you do any more.
If you have a scanner, check the freeze frame and see when this code is being thrown out.

https://www.youtube.com/watch?v=PXW4PM_UjSs vid is for Mazda 3, but should be close enough. Don't use brake cleaner, get the mode expensive MAF cleaner.
 
So I tried cleaning the MAF sensor but ended having to replace it. Thi was actually the 2nd time Ive replaced it. My previous MAF sensor was actually a Denso that was put in about 2 years ago at the same time my M5s throttle body was cleaned. This was done to clear another CEL. This time I spent the money and went with OEM . So far no more CEL after driving 200+ miles.
 
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