Hi, My 98 ML320 has the check engine light on and it is showing a p0105 map malfunction code.
My question is where is the map sensor? none of the online MB parts stores seem to have them and what does it look like?

Thanks for any help

anyone???

I saw it on oempartsdirect.com. Call Phil, he should be able to get a better price.

MAP sensor, not maf.
Manifold Absolute Pressure.
Don't know if this car has one.

I would expect this car to have a MAF sensor and maybe a MAP as backup.

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1976 BMW 2002- 100k
1995 BMW 325i 175k
1984 Mercedes Benz 300D Turbo Diesel- 270,000 mi

1981 Mercedes Benz 240D- Estimated 300,000+ mi Returned to the earth

It's at the top front of the engine, just inside the passenger side valve cover. It's the electrical piece screwed into the manifold.

One of the common mistakes made in troubleshooting based on diagnostic codes is replacing the indicated sensor before performing basic circuit troubleshooting.

Codes do NOT indicate bad sensors. They DO indicate bad circuits of which sensors are almost always a key part. That is why the code is named for the sensor.

If every diagnostic code that is read were properly analyzed before buying the corresponding sensor, it would probably cut Auto Zone and the other auto supply stores gross sales by 10%. This is why Auto Zone is so anxious to draw codes for free because they will almost always sell a sensor whether it is needed or not.

Good luck.

I know it could be a bad vacuum line, I checked all the lines I could find but none looked bad, I am going to change them anyway.

Could a bad MAF cause this code??

Also why does MB parts department say this car doesn't have a map sensor?

I've seen this same pressure sensor on my other MB's. I think MB list is around $70, which is only around 100,000% profit.

On my 98 ML320, the MAP sensor is mounted on the firewall, driver's side, with a vacuum hose going down to the distribution fitting on the back of the engine.

that distribution fitting is definitely an item that should be replaced as it will get hard and leak with age. part number 112-018-02-09, about 10 bucks.
from a previous post topic rough idle

Take a close look at the vacuum distribution block mounted at the back of the intake manifold. It has a small pitot tube integral to it that affects the signal to the PCM It pulls straight up after removing the various lines from it and I am sure you will find it brittle and maybe broken like mine. A picture is attached.

Other things that can affect idle would be a partially stuck open EGR valve.

Crud build up around the throttle body blade can affect idle speed as well.

the power steering has a pressure sensor that signals the PCM for more idle speed. The AC is an electronic input I think,
Attached Thumbnails

Thanks for the replies, but the only trouble i am having with the car is the check engine light (p0105) , the car runs and idles perfect.

I can't see any attached pics, am i doing something wrong??