It sounds like you're guessing at things.

P0106 relates to the MAP sensor, which reads manifold absolute pressure. It has nothing to do with the intake plumbing or the MAF sensor.

On your engine it's a little sensor mounted on the front of the engine off a little bracket, relatively close to the idler pulley. There is a vacuum line on it and an electrical connection and those can fall off, which will trigger the code.

If I can find you a picture, I'll post it, but that should be enough to help you locate it. Be sure the vacuum lines are connected and the harness connector is firmly plugged in, follow the vacuum line to be sure it isn't disconnected on the other end or broken. Inspect the wires to be sure they aren't damaged.

Good luck.

 

Here is a pic of the sensor itself. IIRC the harness connector faces up and the vacuum line plugs in from the rear (the nipple faces the engine).

If everything is plugged in and not damaged, then I would replace the sensor. Not expensive online, the site I got that pic from (autohausaz.com) sells it for $35.

 

And here is a pic of how it is situated on the engine. I'd forgotten I took this pic, this is the M112 engine, but it's the same configuration as your M113. The MAP sensor is circled in red. You will likely have to remove the engine cover to get to it.

Oh, and if you have to replace it, importec.com has it for $27, best price I've seen.

Good luck.

 

God bless you...im going to check this now...the dealer told me these cars dont have a MAP sensor and the MAF sensor is considered the MAp sensor, didnt make sense to me either. and then doing research online, i saw where a benz tech told a person with similar issue to change the o2 sensors. will go check on this right now and hopefully can get this fixed

 

...the dealer told me these cars dont have a MAP sensor and the MAF sensor is considered the MAp sensor,...

There is several cryptic references to the MAF having an internal MAP sensor in WIS and no MAP sensor in EPC for some 430's. Which could mean a new MAF for you..maybe.

If you want to toss your VIN at me I can try to isolate it down a bit for you.

 

Check for a broken vacuum line/hose. I've replaced the plastic lines over the years on some models. Sounds like a simple fix.

 

WDBNG70J62A288721 is the vin

 

Your motor is 113.941. WIS shows no MAP on 113.941 for 220.070/.170

However.. They do show a B28 Pressure Sensor on 113.941 for 220.070/170 with option code 494a ( USA version)

So.. best bet, take CheckCodes pic out to the car and see if a sensor is where the pic says there might be one. If its there, cheap to replace and see if codes go away. If its not... Hello Dollarship, or ebay or other source for a MAF.

Part number for reference for the MAF is A 113 141 01 25 good for that model from MY01 onward.
The MAP sensor is A 005 153 50 28

 

I will totally agree with you that the EPC is awful for looking up some things (I really sympathize with the poor parts counter guys trying to learn it!). However, I did find it with his VIN under the engine section, sub 14 (intake and exhaust manifolds), sub 105 (air pump), with a notation for model year 01 and newer, which would certainly include his car (there is another part number for the 113.941 for years leading up to 01). And since he has a US version car, that makes total sense, so I'd bet good money that he has the MAP sensor, just where I noted.

Sounds like he is still struggling, so I'll respond to his last post as well.

 

i checked the hoses and true enough one of them was bad and i have had that fixed but car still vibrates at idle at red light and gas mileage is horrible. I changed the maf sensor but i did put in a used one which i am guessing could have been bad??? or could it be something else? or will the MAP sensor also cause this? the mechanic said the MAP sensor looks good and will not cause the vibration and bad gas mileage, so we didnt bother changing it. He cut off the check engine light so will see if it comes back on and what codes it will shoot

 

Lambo, you're still not focusing on the MAP sensor, so let me try to explain things a bit differently.

The MAF (mass airflow sensor, air mass sensor) on your car is in the intake stream and measures the total amount of air entering the intake manifold. Your MAF also incorporates the IAT, the intake air temperature sensor. Both of these measured values are passed to the ECU, which makes a determination (together with data passed from many other sensors) about how much fuel to shoot into the injectors, how much to advance the timing, etc.

The MAP sensor measures the absolute manifold pressure by means of a vacuum line that connects to the manifold. Pretty much it's reading how much vacuum there is, which itself discloses quite a bit about the engine state at any given moment. The MAP is wholly independent from the MAF, but the values it reads are also passed to the ECU and used in the complex algorithms for engine management. If this sensor is malfunctioning -- or the vacuum line on the back of it is disconnected -- then the car will run poorly, mileage will suffer, etc., just as you have described. (Of course, both of those things will also be true when many other things malfunction, including the MAF. However, your DTC, P0106, specifically targets the MAP sensor, not the MAF.)

So, please, refer back to the picture I posted above of the actual engine. Open your hood, remove the engine cover, and locate the air pump (the big black circular looking thing dead center at the top/front of the engine). Now look left from it and just above the idler pulley, look for the little bracket that is in the red circle in the picture. That little valve is right on the end of it. Be sure the electrical connector is plugged in, and check the wires for any damage. If that's good, then reach behind it and feel to see if a vacuum line is plugged into it. If the vacuum line is connected, then follow it back to be sure it is not broken or disconnected on the other end, which plugs in directly to the manifold. However, where it plugs in is buried behind the air pump and below the larger hose that feeds the diverter valves, so you may have to really dig around in there to find it.

Now, if there is no vacuum line attached to the MAP sensor, then get a good flashlight and find the disconnected line and plug it in. Of course if the nipple is broken off in the hose, you won't be able to plug it in and will have to replace the sensor.

It seems that much of the time the P0106 code results after an unrelated repair job, such as a water pump or idler pulley, when the bracket is disturbed or inadvertent pressure is placed on the vacuum line. Sometimes it just knocks the hose off, sometimes it cracks the hose, and sometimes it breaks the plastic nipple off the back of the sensor. In the latter case you have to replace the sensor.

I hope that helps. I wish I were close to you, because I could come over and we could bang this out in about seven minutes.

Good luck. Post back, ask more questions if you need to, etc. I'm nearly as anxious as you to get this fixed so you can pass the smog test and get your driveability and fuel economy back!

 

thanks so much. i actually found the MAP sensor exactly where you stated and one of the hoses was bad so i had a mechanic change it and clear the check engine light. But car still runs and idles rough and gas mileage is still horrible. I actually have a new MAP sensor i ordered from the local autozone for $40 (duralast brand) but we never installed because he (the mechanic) said it is most probably the hoses that were disconnected causing me problems but even after connecting the hoses back, car runs rough. So i am just stuck right now, its been 2days and CEL is not yet back on but i hope it comes back and we can try to trace down the exact problem. I love this car, have owned it since 09 and most reliable car i have ever owned. I also have an 03 745li which is a POS and also an audi a8L i purchased last year and barely driven that because its problems after problems, just ready to get this baby back in good mechanical condition

 

I would clear codes and dump a bottle of Techron in the tank together with a bottle of Stabil Blue, then drive it about 25-35 miles, holding it in 4th with a few bursts up to 80+, at least if you can do so safely. (4th gear lets the engine rev higher so you don't need to gather serious speed.)

Then check it for codes and see where you are. If you still have the P0106, replace the MAP sensor. But I wouldn't use the autozone one, I'd buy the one from Importec, it's cheaper and Bosch.

Good luck.