Code P0172
Code P0172
I getting code po172 , I have searched but only find info for the non E55K , so far I changed the front 02 sensors and the spark plugs. Any help is greatly appreciate.
thanks
thanks
if you read what i wrote it says i did a search but could not find anything for the E55K engine just the NA engines with a mass air flow sensor that a E55K does not have.
thanks anyway
thanks anyway
I know want it means ,I'm just looking for advice on a possible fix , maybe some one here had this problem, just looking for help, i thought that's what the forum was for to help each other .
Super Member


Joined: Jan 2007
Posts: 979
Likes: 38
From: South Africa
2018 E63s AMG (Current) 2011 CL63 AMG (Sold) 2005 CLS55 AMG (Sold) 2004 C32 AMG (Sold)
I'm guessing you got no wideband to confirm that the bank is running rich.. Maybe it was a once off that threw the code. Have you tried to clear the code and drive the car again as see if it returns?
thanks
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Super Member


Joined: Jan 2007
Posts: 979
Likes: 38
From: South Africa
2018 E63s AMG (Current) 2011 CL63 AMG (Sold) 2005 CLS55 AMG (Sold) 2004 C32 AMG (Sold)
Hi , I have done a reset but it keeps coming back, I have replaced the spark plugs, the front o2 sensors, I also have tried looking for a vacuum leak, and checked fuel pressure , I'm starting to think a fuel injector, I'm still doing my research but also looking for any advice.
thanks
thanks
If you want to keep tackling this yourself, then you say you already have done spark plugs.. Then that leaves swapping the coil packs from bank 1 to bank 2.. Swap them over and see if your error code persists or it switches over to the other bank.. Then you know its a coil pack
What's the description of P0172? When you scan for codes it'll say something something rich/lean, etc.
Are there other codes?
Does the car run different?
Most CEL codes aren't model specific. So if you find someone with E350 or E500 that had same code, chances are that's the same issue. And for what it's worth, changing spark plugs almost never fixes a code on modern cars. You'd have significantly decreased performance if sparkplugs were that bad.
Are there other codes?
Does the car run different?
Most CEL codes aren't model specific. So if you find someone with E350 or E500 that had same code, chances are that's the same issue. And for what it's worth, changing spark plugs almost never fixes a code on modern cars. You'd have significantly decreased performance if sparkplugs were that bad.
Last edited by sonicc; Jul 23, 2020 at 03:31 PM.
Fixed
Thanks for all the help, after more testing found a bad (leaking) fuel injector , replace all injectors from fcpeuro and it's all good now. Running smooth
Fixed
Thanks for all the help, after more testing found a bad (leaking) fuel injector , replace all injectors from fcpeuro and it's all good now. Running smooth
Super Member


Joined: Jan 2007
Posts: 979
Likes: 38
From: South Africa
2018 E63s AMG (Current) 2011 CL63 AMG (Sold) 2005 CLS55 AMG (Sold) 2004 C32 AMG (Sold)
I used to get that code, and my oem cats were shot, clogged. Went aftermarket with no cats, made more power and no more codes.





