Crazy MPG readings
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Junior Member
Joined: Aug 2020
Posts: 63
Likes: 8
From: Texas USA
2008 ML 350 4Matic
Crazy MPG readings
2008 ML350 4Matic I replaced the MAF, cleaned the Throttle body while doing that and now I am reading P1071,P1072 and P1075.
- Cleaned the new MAF (odd but just to complete the check list)
- Cleaned the K&N Filters
- Cleaned the Throttle Body again
- Replaced the Throttle body Elbow (Broke when cleaning the TB)
- Replaced the PCV and Cam Shaft plugs.
The cluster MPG reading when IDLE is going down fast to 9.0 MPG, when driving it goes up slowly to 20.6 and I am assuming it will go up further if I drive longer (What is that???)
Any help is greatly appreciated, I am running out of options here.
- Cleaned the new MAF (odd but just to complete the check list)
- Cleaned the K&N Filters
- Cleaned the Throttle Body again
- Replaced the Throttle body Elbow (Broke when cleaning the TB)
- Replaced the PCV and Cam Shaft plugs.
The cluster MPG reading when IDLE is going down fast to 9.0 MPG, when driving it goes up slowly to 20.6 and I am assuming it will go up further if I drive longer (What is that???)
Any help is greatly appreciated, I am running out of options here.
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
When you get these codes on both banks it is usually a broken or partially split vacuum hose anywhere on the eng.
Take off the eng. cover and go to work, especially at the rear of the eng.
Take off the eng. cover and go to work, especially at the rear of the eng.
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
Yes, the mixture of gas and air are precise. If there is a broken hose, more air is being fed into the mixture. The ECM recognizes this and adds more fuel to compensate the additional air, hence bad mileage.
