2003 C32 MAP Sensor Location
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2003 C32 AMG
2003 C32 MAP Sensor Location
I have a 2003 C32 that has rough idle at start and after it warms up, intermittently. It does intermittently return to norma,l as well. It doesn't seem to affect the acceleration, just idle. It sometimes runs close to stalling, others seems to hunt for a steady idle and surges to 2000 RPM. I have check the codes and I get a P0105, MAP Sensor. I have checked for any vacuum leaks and have concluded I need to change out the MAP Sensor. All exploded views of the engine on line show it up front, but I think that is for a C320. With the supercharger, I can't locate the MAP sensor and have looked for a vacuum line and wiring harness to no avail. I have yet to start removing anything other than the engine cowling. Can some one point me to the location and let me know if it is difficult to replace. I have done spark plugs, coils and valve cover gaskets as well as AC vent motor change outs in the dash, so you have an idea of my experience level.
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2002 C32 AMG, 2013 GLK 350/4, 2015 E63S AMG Wagon
Please learn to use the Search function. It will be your best help here. Searching the C32 area for "MAP location" would point to this: https://mbworld.org/forums/c32-amg-c...-location.html
And here is a diagram for you. item#45
And here is a diagram for you. item#45
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2003 C32 AMG
Thanks Lenin. I had searched and found that thread, but did not see the diagram. Not knowing exactly where "On the Intercooler below the S/C toward the rear...." actually was leading me, I thought a diagram would help.
Have you done this before and does it require removal of a bunch of things to access it?
Have you done this before and does it require removal of a bunch of things to access it?
MBWorld Fanatic!
Joined: Mar 2004
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Likes: 27
From: North NJ
2002 C32 AMG, 2013 GLK 350/4, 2015 E63S AMG Wagon
Thanks Lenin. I had searched and found that thread, but did not see the diagram. Not knowing exactly where "On the Intercooler below the S/C toward the rear...." actually was leading me, I thought a diagram would help.
Have you done this before and does it require removal of a bunch of things to access it?
Have you done this before and does it require removal of a bunch of things to access it?
Here is another diagram for you. You can see an area circled in read. That is where the MAP sensor goes. I never had a issue with the MAP sensor and only swapped it out once (just in case) when I was doing other work in that area. You may be able to replace it by taking the driver side air filter and the intake manifold. And if you have small hands (or know someone that does), then give it a shot.
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2003 C32 AMG
This is great. Thanks!. I am trying the cheap items that I can do before getting a Star analysis. I was tempted to unplug the MAP sensor electrically and see what happens. If it is bad it would behave the same way. If not I have a different problem. That may be difficult with its location and not worth the effort.
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From: North NJ
2002 C32 AMG, 2013 GLK 350/4, 2015 E63S AMG Wagon
Whatever you do, only buy genuine MB sensors. I've seen way to many people on the forum buy cheap ebay electrical parts (CPS, MAP, IAT) only to repeat the job again with the OEM part.
Also, can't you connect your phone with the appropriate OBD2 cable and an app to monitor boost? You should be able to see if the reading is jumping all over when it should not be, even on a slow OBD2 connection.
Also, can't you connect your phone with the appropriate OBD2 cable and an app to monitor boost? You should be able to see if the reading is jumping all over when it should not be, even on a slow OBD2 connection.
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2003 C32 AMG
Good idea. I need to get the adapter and load an app first. I'll get one this weekend and see what it tells me about manifold pressure. I agree on the OEM parts. I don't want to have to redo work.
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2003 C32 AMG
I got the adapter and watched the boost. It jumps around along with the idle. As the idle steadies (still high 1100 rpm) the boost is steady, when idle jumps up around 2k, boost drops (more negative). As I am driving and accelerate, boost is positive and is consistent with acceleration until gear changes, then drops. I have off and on CEL throwing P0105 code. I am not sure if the sensor is bad and causing idle fluctuations or I have another issue causing idles fluctuations and sensor is reading normal pressure fluctuations.
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2003 C32 AMG
The whole idle thing ended up as a significant repair. It was a hole in the intake tube of the supercharger inter cooler caused by a coolant leak in the intercooler. Over time the hot coolant was eating away at the air intake hose on the bottom out of view. This probably took several years of leaking. I had always notice a use of coolant over several months, but neither I or the dealer were able to find a leak. Now I know.
