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Story here but I will do my best to explain. Working on a…

Customer Question
Hi, long story here but...
Hi, long story here but I will do my best to explain.
Working on a 2009 C63 with 167k miles.
The vehicle was sent to me by another shop. A used engine was installed but I do not know anymore background info.
The vehicle has headers with NO front or rear catalyst.
The engine runs but poorly. On acceleration the power cuts in and out very badly one second and accelerates normally the next. It feels as if the throttle is snapping shut and opening rapidly.
Also the idle is poor
Submitted: 5 months ago.Category: Mercedes
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Customer reply replied 5 months ago
Also the idle is poor.So far I have replaced the intake manifold assembly, flashed the ME to a stock tune, replaced the front o2 sensors, replaced the air filters, smoke tested the intake system multiple times for leaks, and replaced the cam adjusters and bolts. I did not replace the diamond coated washers between the cams and adjusters (although I should have). I did set the timing with the proper tools and I did inspect the cams and lifters for wear.I have also reset and performed all adaptions multiple times with xentry (cam timing adaptions, throttle adaptions, sensor rotor adaption, etc).All parts used were genuine MBZ.I do get faults for the air mass not correlating with the throttle angle and I get intake cam adjustment faults on both banks.When driving the engine pulls one moment and the next cuts in and out badly as if the throttle is snapping shut and re-opening. At idle it is okay one second and then either rough or too high (1000 rpms) and will stall randomly.I replaced the front oxygen sensors because the looked fouled out, as do the rears currently. I assume because the car has no catalysts.
Customer reply replied 5 months ago
Also I have inspected the flex plate sensor rotor for damage and found none.
Answered in 3 hours by:
3/11/2018
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago
Lou P. master tech
Lou P. master tech, Mercedes Technician
Category: Mercedes
Satisfied Customers: 6,259
Experience: 20 years Master Certified excellent fix rate and have access to factory wiring, and instructions.
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Hello my name is***** am going over your request now and will reply back soon with some info OR a few questions that would help me better determine how to help you. Keep in mind I have no idea of your technical ability or what you do and do not already know. So the more info you can tell me the better. I have been on the site for almost ten years and have oustanding 5 star ratings so trust that I will do everything I can to get you taken care of, Lou
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Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago
Can you give me the fault code numbers and or screen shots showing the fault codes?
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Customer reply replied 5 months ago
I can but not until tomorrow
Customer reply replied 5 months ago
Also my technical ability is high and tool availabity is very high.
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago
OK sounds good I will be online all week and I figured your technical ability was high that is just my standard opening sentence LOL I get a lot of I already know that and you didn’t tell me anything I didn’t know LOL
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Customer reply replied 5 months ago
I will provide the fault codes numbers tomorrow of course. I did look them up in WIS and followed Xentry test plans which were not helpful. They basically said Check for false air, which I have done several times. The M156 has no actual values for air mass sensors.Although the running problem is so drastic it feels way beyond a small vacuum leak, etc. 1/2 the time it dies immediately upon start up.
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

ok sounds good.,

do you have a smoke machine?

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Customer reply replied 5 months ago
I smoked the intake several times and found no leaks.I also removed the air pump hose and tried to blow through the air pump check valves to make sure they were not stuck open.Fault codes:
See attached photoP3729 The measured left air mass is implausible compared to the position of the throttle valves (P010B)P1351 The measured right air mass is implausible compared to the position of the throttle valves (P0101)P0271 Continuous camshaft adjustment (right): incorrect position of intake cam (P0011)P0275 Continous camshaft adjustment (left): incorrect position of the intake cam
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

did someone install aftermarket air filters in this engine?

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Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

ok you said something strange that i thought i read, this engine DOES have mass air flow sensors.

there are in the intake pipe. the one on top of the engine.

can you send me a few pictures of the top of the engine.

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Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

oh NO actual values, sorry , misread

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Customer reply replied 5 months ago
the engine does have air flow sensors. They are however a strange type and Xentry, Autologic, or any other scan tool does not have an actual value reading that you can view for them.Correct no actual values
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

ok, there is a way to see them, i forget at the moment but i can try through my sds later tonight, you have to go to tests or fault codes and perform the test and it will show you the values.

i used to have issues where people installed K&N air filters and there was TOO much airflow, can you verify the air filters?

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Customer reply replied 5 months ago
Do you know if the rear oxygen sensors are used for mixture calculation by ME9.7 or if they are only to monitoring the front sensors and converters?I can’t seem to find that info
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

primarily to monitor cats.

the front ones adjust as well as the mass and map

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Customer reply replied 5 months ago
I went through every possible menu of the SDS and found no possible way to view the air mass readings. I even followed the test plans for them and it just gives pin out information which I followed.The air filters have been replaced by me and are original
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

ok,

gotcha.

and you dont know what happened before this engine right?

can you see the engine number on the side of the block? should be near the motor mount bracket on one side. ill have to see where.

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Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

sorry see you got new air filters as well.

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Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

ok, i see you replaced the cam adjusters, but did you replace the solenoids?

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Customer reply replied 5 months ago
I was told the old engine had a knock.... but I am unsure since I did not see the car previously and I trust no one but myself.
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

thats for sure lol

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Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

ok, so when you said you followed the test plans for the mass air flow, did you process the fault codes by pressing f3 on the fault code?

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Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

if you have access to the internet with your scan tool maybe download teamviewer and I can jump on your scanner and walk through it with you.

i am wondering if the engine is correct for the car.

you cant just slap any old M156 amg engine in any car.

at least im pretty sure.

sorry I dont have a quick fix for you.

this will take some diag, i am willing to help,

let me know your thought.s

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Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

teamviewer is free for use.

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Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

hey make sure the mass air flow sensors are facing the correct way just to be sure, the air has to flow through them the correct way.

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Customer reply replied 5 months ago
The air mass sensors are positioned properly.I do have a SDS with teamviewer installed already. But it may be hard to do in the middle of my shop day.Yes I processed the faults with SDS test plans.
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

ok,

do you stay late? ever?

i am on all day every day basically

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Customer reply replied 5 months ago
I stay late often but I am on the west coast. I can log you on between 5pm and 6:15pm Pacific
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

k that might work.

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Customer reply replied 5 months ago
Or I can come early tomorrow morning 7am Pacific
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

i will be traveling at that time.

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Customer reply replied 5 months ago
I can set up SDS around 4:30 Pacific today if that works for you.Team viewer 7 or 13?
Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago
That might work, that would be 6:30 my time , ill send over the offer
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Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago
It might make you updste to the newest one anyways
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Mercedes Mechanic: Lou P. master tech, Mercedes Technician replied 5 months ago

and no worries if we cant figure something out i have no problem releasing the questions to others,

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Customer reply replied 5 months ago
Did you already refer me to someone else?
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