MAP sensor: No readings
Thread Starter
Newbie
Joined: Aug 2016
Posts: 9
Likes: 0
From: Estonia
CLS63 AMG 2014
MAP sensor: No readings
Hi
I think im having an issue with my MAP sensor on my cls55 engine.
Its giving out a constant reading of -38 hPa no matter how much I rev it.
I even replaced it with a new one, still no proper readings
No faults stored in ECU
Anyone encountered something like this before?
I think im having an issue with my MAP sensor on my cls55 engine.
Its giving out a constant reading of -38 hPa no matter how much I rev it.
I even replaced it with a new one, still no proper readings
No faults stored in ECU
Anyone encountered something like this before?
Last edited by tobler; Aug 17, 2016 at 10:22 AM.
Thread Starter
Newbie
Joined: Aug 2016
Posts: 9
Likes: 0
From: Estonia
CLS63 AMG 2014
The car is all stock. no tunes no pullys.
other problems:
-The intercooler pump needs to be replaced as the intake temp is too high and im experiencing SC shutdowns.
-I reckon the sparkplugs need replacing aswell since the engine vibrates a bit at 900-1700rpm when cold (in D and P) and It prolly never been done ( 86k on the clock ).
I think my car doesnt pull as well as it should ( though I havent tried any other 55's). I guess I put it on a bad Intercooler pump and sparkplugs for now.
And I cant think of any reason why these 2 problems would be related to my bad MAP readings.
Oh and yea sensor was a hell of a *unt to replace
other problems:
-The intercooler pump needs to be replaced as the intake temp is too high and im experiencing SC shutdowns.
-I reckon the sparkplugs need replacing aswell since the engine vibrates a bit at 900-1700rpm when cold (in D and P) and It prolly never been done ( 86k on the clock ).
I think my car doesnt pull as well as it should ( though I havent tried any other 55's). I guess I put it on a bad Intercooler pump and sparkplugs for now.
And I cant think of any reason why these 2 problems would be related to my bad MAP readings.
Oh and yea sensor was a hell of a *unt to replace
Thread Starter
Newbie
Joined: Aug 2016
Posts: 9
Likes: 0
From: Estonia
CLS63 AMG 2014
Trending Topics
MB World Stories
The Best of Mercedes & AMG
8 Oddball Mercedes Ideas That Actually Made it to Production
Verdad Gallardo
Dubai Tuner Gives the Mercedes G-Class An Entirely New Look
Verdad Gallardo
Six Gift Ideas Your AMG Loving Dad or Grad Will Cherish
7 Craziest Things AMG Gas Ever Built
Verdad Gallardo
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know
Verdad Gallardo
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Thread Starter
Newbie
Joined: Aug 2016
Posts: 9
Likes: 0
From: Estonia
CLS63 AMG 2014
haha, good question. its not that easy to test.
BUT .. I had it unplugged (by accident) for a few days.
It gave me a CEL and it felt as if the fuel mixture was running rich.
And a fault code was stored in the ECU. After that I replaced the sensor with a new one and deleted the fault codes.
And the new sensor worked just like the old one: not getting any correct readings
BUT .. I had it unplugged (by accident) for a few days.
It gave me a CEL and it felt as if the fuel mixture was running rich.
And a fault code was stored in the ECU. After that I replaced the sensor with a new one and deleted the fault codes.
And the new sensor worked just like the old one: not getting any correct readings
Member
Joined: Mar 2015
Posts: 99
Likes: 12
E55 w211
The reason I ask is if you have a wire pinched or chafed and shorted to ground it could be giving you the oddball errors.
Try turning the ignition on and monitoring the sensor reading without the engine running, it should show you atmospheric pressure.
Try turning the ignition on and monitoring the sensor reading without the engine running, it should show you atmospheric pressure.
Thread Starter
Newbie
Joined: Aug 2016
Posts: 9
Likes: 0
From: Estonia
CLS63 AMG 2014
I definately saw the sensor working as the voltmeter was reacting to different levels of vacuum.
So my next step will be to test the wiring of the map sensor, especially the middle pin wire of the MAP sensor, as it is the one to send signals to ECU.
fingers crossed for the wire to be broken / pinched .. otherwise im running out of ideas
Thread Starter
Newbie
Joined: Aug 2016
Posts: 9
Likes: 0
From: Estonia
CLS63 AMG 2014
a little update on the matter.
the signal cable of the MAP sensor is alright. Tested with a voltmeter from both ends ( MAP sensor plug & ECU plug ).
So next thing I'll do is trying to measure the signal from the ECU plug with a voltmeter with running engine and boost. who knows, maybe my diagnostics tool is acting up (no readins) and Im chasing after ghosts
the signal cable of the MAP sensor is alright. Tested with a voltmeter from both ends ( MAP sensor plug & ECU plug ).
So next thing I'll do is trying to measure the signal from the ECU plug with a voltmeter with running engine and boost. who knows, maybe my diagnostics tool is acting up (no readins) and Im chasing after ghosts
