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2001 Mercedes-Benz S600 Question: 2001 S600 Mercedes Misfires

 

Question

eliebenz, Lawrence, MA, June 13, 2010, 10:09
 Rookie

Diagnostic Trouble Codes:
P0311 P0312 P0308
P0310 P0300
Local Mercedes dealer's diagnostic included compression
test's result was no compression in Cylinders #11 & #12
and they recommended to take heads off for further analysis.
I had the left coil bank replaced and no luck.
My question is:
IS A FAULTY MASS AIR FLOW (MAF) SENSOR
CAUSING THE MISFIRE/ERRATIC/ROUGH ENGINE RUNNING
SINCE THE MASS AIR FLOW SENSOR MEARURES THE ACTUAL AMOUNT OF AIR ENTERING THE MOTOR AND THE ENGINE CONTROL MODULE (ECM) IS TAKING THE WRONG INFORMATION AND DELIVERING INCORRECT VOLUMES OF FUEL TO CYLINDERS #11 & #12?

2 Answers
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  • Answer #1

    Visitor, January 18, 2011, 18:19

    Was there a check engine light telling you that the voltage coming from the mass air flow sensor was out of range?

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  • Answer #2

    DerMachtigBenz January 25, 2013, 13:12
     Rookie

    If you actually did receive a message of "no Compression" in 2 adjoining cylinders, I cannot see how replacing parts will address the issue. If you have no compression, it is a signal that you have a leak... Head Gasket, valves burnt, bent or mis-seated, hole in piston, cracks in head or block, all not a lot of fun.
    However, as the cylinders are adjoining, a blown head gasket (the least expensive of the above) is quite possible. Get the side of the engine clear by removing coil bank, etc, and pull the plugs. Put a compression tester in "free flow" mode (unlocked) and watch how the pressure moves on each cylinder VISUALLY. Dont forget to pull the hot lead on the OTHER coil bank first, or engine could start while testing.

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