DTC P0172 P0175
Thread Starter
Junior Member
Joined: Jun 2007
Posts: 41
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From: Vancouver Canada
1991 190E:1998 E320 4Matic wagon : 2000 E320 4Matic
DTC P0172 P0175
I'm attempting to help one of my Merc group buddies with a CEL and codes are P0172/P0175 both banks running rich. From reading posts I think (after checkingf or vaccum leaks) that MAF may be a consideration . He drives a E320 2003 with 80000Km or 50000 miles on it . There are no symptoms (as yet ) . CEL was intermiitent at first but now constant. Before purchasing the new MAF (insert only, no housing) I was thinking of first swapping my 2000 E320 MAF with his and see wehat happens .. Any experience out there.
Thanks..chiro
Thanks..chiro
Super Member
Joined: Apr 2005
Posts: 666
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From: Boston, MA USA
03 E320 -wife's car now; 07 Porsche Boxster S - my toy
I'm attempting to help one of my Merc group buddies with a CEL and codes are P0172/P0175 both banks running rich. From reading posts I think (after checkingf or vaccum leaks) that MAF may be a consideration . He drives a E320 2003 with 80000Km or 50000 miles on it . There are no symptoms (as yet ) . CEL was intermiitent at first but now constant. Before purchasing the new MAF (insert only, no housing) I was thinking of first swapping my 2000 E320 MAF with his and see wehat happens .. Any experience out there.
Thanks..chiro
Thanks..chiro
Here's something from a site (http://www.autotap.com/DIY_booklet.html) that makes OBD2 scanners:
"P0172 and/or P0175 are rich codes and indicate a general rich air/fuel condition. The underlying cause may be anything that increases fuel delivery, such as excessive fuel pressure, a defective fuel pressure regulator or plugged return line, or leaky injectors. Decreased airflow from a dirty air filter or restricted air intake misleads the mass airflow sensor or engine management system into believing the engine is using more air or is under more load than actual."
Regards,
paul...
Last edited by paulv; Jun 25, 2008 at 02:13 PM.
Thread Starter
Junior Member
Joined: Jun 2007
Posts: 41
Likes: 0
From: Vancouver Canada
1991 190E:1998 E320 4Matic wagon : 2000 E320 4Matic
MAF was the problem
Well, we switched MAf sensors and I got the trouble codes. We then bought MAF from ebay and it was Bosch original,,installed it, cleared the codes and no further problem .The maf sensor was the same but the connection for the electrical was a bit different,however all worked out and saved big $$$.
MBWorld Fanatic!
Joined: Dec 2006
Posts: 6,499
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From: Europe
223.168 & 213.012 & 906.633 & 214.005
Hopefully it was a Bosh original sensor instead of "Bosh original like" with some small text telling "made in China". Someone just reported problems with some MAF sensors sold at eBay. Sure your sensor can be a real one, just wanted to repeat the warning from this owner who had a bad part (that only worked for a short time).
