Need HELP: CEL P0171, P0172, P0174, P0175
Thread Starter
Senior Member
Joined: Dec 2007
Posts: 386
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From: New York
2010 C300 4MATIC
Need HELP: CEL P0171, P0172, P0174, P0175
Hey Guys,
Recently the CEL and these four codes popped up on my OBDII reader: P0171 System too Lean (Bank 1), P0172 System too Rich (Bank 1), P0174 System too Lean (Bank 2), P0175 System too Rich (Bank 2). Moreover, after installing the CLK55 AMG Air Box on my CLK430, every time I floor the car I seem to lose power after 5000 rpm and redlines through every gear. Before, installing the intake I made sure to clean the MAF according to the diy a member posted on this forum. I just want to know what could possibly be wrong with my car?
Thanks,
Steve
Recently the CEL and these four codes popped up on my OBDII reader: P0171 System too Lean (Bank 1), P0172 System too Rich (Bank 1), P0174 System too Lean (Bank 2), P0175 System too Rich (Bank 2). Moreover, after installing the CLK55 AMG Air Box on my CLK430, every time I floor the car I seem to lose power after 5000 rpm and redlines through every gear. Before, installing the intake I made sure to clean the MAF according to the diy a member posted on this forum. I just want to know what could possibly be wrong with my car?
Thanks,
Steve
Thread Starter
Senior Member
Joined: Dec 2007
Posts: 386
Likes: 2
From: New York
2010 C300 4MATIC
I did some research and it can possibly be a MAF or a vacuum leak. How do I isolate the issue because I don't want to spend money on something that does not need fixing?
Thanks,
Steve
Thanks,
Steve
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From: KCMO, but Houston is my home.
01 CLK 430
You said you cleaned the MAF, so I would make sure that everything went back together properly and all the connections are nice and tight. Its easy for things to get knocked out of whack when working in such a small space.
Thread Starter
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From: New York
2010 C300 4MATIC
The codes appeared before the install of the new intake. I triple checked that everything is completely clamped and locked up; however, I still get the codes.
Thanks
Thanks
Super Member
Joined: Mar 2005
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From: North of Boston
A very common issue with the airbox is that it is not seated into the MAF housing correctly. When placing the airbox, the rear of the intake must be pressed into the MAF housing first (check that it is totally engaged) and then the front is gently lowered onto the front clips....hope that helps...replacing the MAF is a relatively cheap DIY fix. Get a OEM Bosch from Autohuaz, not an ebay knockoff.
Last edited by cindyclk; Jul 21, 2010 at 07:57 AM.
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Thread Starter
Senior Member
Joined: Dec 2007
Posts: 386
Likes: 2
From: New York
2010 C300 4MATIC
MBWorld Fanatic!
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From: Nebraska
99CLK320,
There is some way to bench test the O2 sensors and I think there was a post somewhere about it. Do a Search. MarcusF may know. I was not successful with a MAF sensor cleaning. I replaced the entire unit and found out after the fact that you can just replace the sensing element for less $ than buying the entire unit. autohausaz has it and you may have to call to get it. All you need is a torqx drive with a hole in the center to remove the sensor from the housing.
Thread Starter
Senior Member
Joined: Dec 2007
Posts: 386
Likes: 2
From: New York
2010 C300 4MATIC
There is some way to bench test the O2 sensors and I think there was a post somewhere about it. Do a Search. MarcusF may know. I was not successful with a MAF sensor cleaning. I replaced the entire unit and found out after the fact that you can just replace the sensing element for less $ than buying the entire unit. autohausaz has it and you may have to call to get it. All you need is a torqx drive with a hole in the center to remove the sensor from the housing.
Thanks
Super Member
Joined: Mar 2005
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From: North of Boston
http://www.autohausaz.com/search/pro...02&cid=22@Fuel %26 Air System&gid=5068@Air Mass Sensor
If you want to do the sensor only, give them a call.
If you want to do the sensor only, give them a call.
Super Member
Joined: Mar 2005
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From: North of Boston
The MAF works with the computer to create the correct air gas mixture. If it is bad the oxygen sensors then detect screwed up mixes. Getting a genuine (not ebay) MAF sounds like the best advice in your situation....my 2 cents
Thread Starter
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From: New York
2010 C300 4MATIC
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mgLipGD
Thread Starter
Senior Member
Joined: Dec 2007
Posts: 386
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From: New York
2010 C300 4MATIC
NEED HELP ASAP
CAR IS IN COMPLETE LIMP MODE! How do I isolate the issue to see if it is a MAF or and O2 sensor? I do not want to buy a MAF and then find out its an 02 sensor.
ANY HELP IS APPRECIATED!
ANY HELP IS APPRECIATED!
