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MB Paul
MB Paul, Mercedes Technician
Category: Mercedes
Satisfied Customers: 3567
Experience:  Qualified Mercedes Benz Diagnostic Technician - 20+ years experience - Workshop Foreman for Mercedes
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2004 c230 p0171 running lean... I have replaced maf,

Customer Question

JA: Hi. What is your issue regarding?
Customer: 2004 c230 p0171 running lean... I have replaced maf, REPLACED ALL VACUM LINES, cleaned throttle. im stuck not passing smog
JA: Sometimes the difference between passing and failing a smog test can be just a few quick repairs. Luckily, the mechanic I'm going to connect you with will have just the information you need to get this fixed fast. How many miles are on the car?
Customer: 150k
JA: Tell me a bit more about what's going on so he can help you best.
Customer: im all out of answers
JA: Are you hoping to fix this yourself?
Customer: here is a list of parts
i replaced
JA: Is there anything else the Mercedes Mechanic should be aware of about your Mercedes?
Customer: yes
JA: What else should I tell the Mercedes Mechanic?
Customer: both o2 sensors replaced
JA: OK. Got it. I'm sending you to a secure page on JustAnswer so you can place the $5 fully-refundable deposit now. While you're filling out that form, I'll tell the Mercedes Mechanic about your situation and then connect you two.
Submitted: 1 year ago.
Category: Mercedes
Expert:  Chad Farhat replied 1 year ago.

Hi , my name is ***** ***** I will be assisting you today

Customer: replied 1 year ago.
2004 Benz c230 po171... Here are the following parts i replaced1x MAF
2x O2 sensors
1x engine harness cable
1x ECUall vacum lines
all gaskets associated with intakeI dont know what else it can be
Expert:  Chad Farhat replied 1 year ago.

oh man sorry to hear that , this one could be a little complicated but i will do my best to help you on it

is the P0171 is the only fault code in it

Customer: replied 1 year ago.
thank you, ***** ***** the only code coming up
Expert:  Chad Farhat replied 1 year ago.

how does the car drive any lack of power , hesitation , how is your fuel mileage ?

do you have a scanner that can read the O2 sensor on live data stream so you can give the short term & long term Fuel trim readings ?

Expert:  Chad Farhat replied 1 year ago.

I like to know the fuel trims readings , it is essential to figure out , if you dont have one now but you can get one ,this post will stay open and we can go back and forth until we can fix it , unfortunately on this one i cant give a quick answer , like how do you program a key fob , but if you willing to work with me and be my eyes & ears ,we can try to figure it out .

Customer: replied 1 year ago.
no loss of power, shaky from engine mounts needing replacement. fuel consumption seems normal. no live scanner unless you consider the bluetooth android torqe app a scanner
Customer: replied 1 year ago.
what reader can I get to get this info?
Expert:  Chad Farhat replied 1 year ago.

there is a bunch , I suggest LAunch , I have a full blown XLaunch pad that do all cars all modules

But LAUNCH SCANNER on there website they offer the software for your individual car for like $50 and you can downloaded on your smart phone , then buy $ 30 OBDII wireless plug connecter available at AMAZON and there you have it ,you can communicate with all the modules in your case 04 benz c230 and read live data, read codes ,clear codes, abs, srs ,etc all modules

let me know


Any scanner that can do that for all vehicles will be $2000 and up but i have a shop I use themon daily basses , you just need your software for the car and use your smart phone instead of the scanner ?

Customer: replied 1 year ago.
ok I will look into it. thanks

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