W204 knock sensor
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W204 c180
W204 knock sensor
Hi all! First of all, sorry for my bad tech english.
To the matter at hand. I have a w204 C180 with m271 engine. It has flashed yellow engine light couple of times. One time while accelerating from 60 to 80 km/h, engine lost its power and started vibrating. All went down in few seconds and wnt away by lifting foot of the gas pedal. Also the engine light turned on and didnt go away. Idling became rough and engine started knockin or pinging.
Went to local carage to make Dtc scan. Diagnose was that knocking amlitude level exceeded bank one, cylinder 2 and 4.
THe carage was not sure is the problem in the knocking sensor or somewhere else and said that they havent done similiar job earlier and cannot give excact estimation on replacing time for the sensor. They said that they can do the job but it will be 500+ euros.
I went and changed the spark plugs because I read from forum that it could solve the problem. Didnt help.
So next thing i guess should be replaceing the sensor. My guestion here is does anybody have some guides on wether the sensor is better accessed from above or beneath the engine?
And follow up guestion is that has anybody had similiar symptoms with their engine and what did you do to fix it?
Thanks in advance for replys.
To the matter at hand. I have a w204 C180 with m271 engine. It has flashed yellow engine light couple of times. One time while accelerating from 60 to 80 km/h, engine lost its power and started vibrating. All went down in few seconds and wnt away by lifting foot of the gas pedal. Also the engine light turned on and didnt go away. Idling became rough and engine started knockin or pinging.
Went to local carage to make Dtc scan. Diagnose was that knocking amlitude level exceeded bank one, cylinder 2 and 4.
THe carage was not sure is the problem in the knocking sensor or somewhere else and said that they havent done similiar job earlier and cannot give excact estimation on replacing time for the sensor. They said that they can do the job but it will be 500+ euros.
I went and changed the spark plugs because I read from forum that it could solve the problem. Didnt help.
So next thing i guess should be replaceing the sensor. My guestion here is does anybody have some guides on wether the sensor is better accessed from above or beneath the engine?
And follow up guestion is that has anybody had similiar symptoms with their engine and what did you do to fix it?
Thanks in advance for replys.
Super Member
Joined: Jun 2017
Posts: 608
Likes: 107
From: Western NC
2009 MB C300 Sport 4matic
https://www.autocodes.com/p0326_mercedes-benz.html
This baseline info about the code that your MB had makes a good read....a couple suggestions about checking the knock sensor connectors, wiring are helpful. I have no info on the sensor location but a Search should help out there. Knock sensors I have changed on other Euro cars are inexpensive, sometimes hidden in the depths of the engine, easy to replace once accessed, and have specific torque tightening specs so they "read" the engine sounds correctly, i.e. knock and ignore other lesser important mechanical sounds.
This baseline info about the code that your MB had makes a good read....a couple suggestions about checking the knock sensor connectors, wiring are helpful. I have no info on the sensor location but a Search should help out there. Knock sensors I have changed on other Euro cars are inexpensive, sometimes hidden in the depths of the engine, easy to replace once accessed, and have specific torque tightening specs so they "read" the engine sounds correctly, i.e. knock and ignore other lesser important mechanical sounds.
Thread Starter
Newbie
Joined: Sep 2023
Posts: 11
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W204 c180
https://www.autocodes.com/p0326_mercedes-benz.html
This baseline info about the code that your MB had makes a good read....a couple suggestions about checking the knock sensor connectors, wiring are helpful. I have no info on the sensor location but a Search should help out there. Knock sensors I have changed on other Euro cars are inexpensive, sometimes hidden in the depths of the engine, easy to replace once accessed, and have specific torque tightening specs so they "read" the engine sounds correctly, i.e. knock and ignore other lesser important mechanical sounds.
This baseline info about the code that your MB had makes a good read....a couple suggestions about checking the knock sensor connectors, wiring are helpful. I have no info on the sensor location but a Search should help out there. Knock sensors I have changed on other Euro cars are inexpensive, sometimes hidden in the depths of the engine, easy to replace once accessed, and have specific torque tightening specs so they "read" the engine sounds correctly, i.e. knock and ignore other lesser important mechanical sounds.
My friend thinks that the sensor is under the intake manifold near the engine mounting bracket. But i dont have the time to dismantle half the engine just to see that cannot acces from there.
Super Member
Joined: Jun 2017
Posts: 608
Likes: 107
From: Western NC
2009 MB C300 Sport 4matic
May possibly be seen from under engine with good LED light.....below side of intake manifold, not under it fortunately. Maybe removing air box components might give you a glimpse at it from above plus wiring attaches from above so you at least can check it's integrity. Sure you have Searched all this...Good luck.
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Joined: Sep 2023
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W204 c180
Funny thing though. Same time with these knock sensor issues i had battety shortage problems. At sunday, I loaded up battety and since then the car has been working like a dream. Havent yet had the time to replace the knocking sensor. But could it be that shortage on battery could have caused the knocking sensor malfunction?
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From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
These cars use a lot of electricity, so a healthy battery is absolutely necessary. If the voltage gets too low, things will start to work improperly and you will get errors that seem totally unrelated.
If you know you have a bad battery, replace that first. You will have to anyway. Then see if your problems return.
If you know you have a bad battery, replace that first. You will have to anyway. Then see if your problems return.
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Joined: Nov 2016
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From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
What year is your car? Later models have turbochargers and direct injection. Direct injection uses two fuel pumps--an electric low-pressure pump (LPFP) in the fuel tank and a mechanical high-pressure fuel pump (HPFP) in the engine. If your battery is failing, there is the possibility that the LPFP was not delivering enough fuel to the HPFP and you were running lean.
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W204 c180
What year is your car? Later models have turbochargers and direct injection. Direct injection uses two fuel pumps--an electric low-pressure pump (LPFP) in the fuel tank and a mechanical high-pressure fuel pump (HPFP) in the engine. If your battery is failing, there is the possibility that the LPFP was not delivering enough fuel to the HPFP and you were running lean.
But makes sense what you wrote earlier. I will get a new battery and see how things go. Also have the sensor just in case the fault comes back.
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W204 c180
Ok so coming back to this matter. I reloaded the battery instead of changeing it. And the car worked beautifullly just until few days a go. The car didnt start in a freezing -15 celsius morning. So I decided now is the time for battery change. All went well and the car started fine. But after 15 km of driving there it was again. The yellow engine warning light and right turning signal stopped working.
so could this be a problem in the altenator? Or somewhere in the wiring?
so could this be a problem in the altenator? Or somewhere in the wiring?
