P0342 (Camshaft Position Sensor "A" Circuit Low)
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2013 GL450
P0342 (Camshaft Position Sensor "A" Circuit Low)
This code came up and now I'm reading about this M278 issue of oil leak from camshaft sensors which seems to be quite common in the M278 engine... I suspect that is what is happening. Going to get it to the shop next week to check.
I have read cases where oil goes so far into the engine harness and people have to replace hardness, ECU, O2 sensor, etc. If the camshaft. If the error has just come up what's the likelihood that the oil has gone far into the harndess?
My plan is to have the mechanic confirm the presence of oil, and if the oil hasn't traveled too far up, change all cam sensors (the newer version of the sensor supposedly has a revised design?) and also add pigtail extensions to isolate the engine harness...
I have read cases where oil goes so far into the engine harness and people have to replace hardness, ECU, O2 sensor, etc. If the camshaft. If the error has just come up what's the likelihood that the oil has gone far into the harndess?
My plan is to have the mechanic confirm the presence of oil, and if the oil hasn't traveled too far up, change all cam sensors (the newer version of the sensor supposedly has a revised design?) and also add pigtail extensions to isolate the engine harness...
Last edited by byroncheung; Nov 3, 2023 at 03:18 PM.
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W212 MY'14 M276-3.5NA @75kMi
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This code came up and now I'm reading about this M278 issue of oil leak from camshaft sensors which seems to be quite common in the M278 engine... I suspect that is what is happening. Going to get it to the shop next week to check.
I have read cases where oil goes so far into the engine harness and people have to replace hardness, ECU, O2 sensor, etc. If the camshaft. If the error has just come up what's the likelihood that the oil has gone far into the harndess?
My plan is to have the mechanic confirm the presence of oil, and if the oil hasn't traveled too far up, change all cam sensors (the newer version of the sensor supposedly has a revised design?) and also add pigtail extensions to isolate the engine harness...
I have read cases where oil goes so far into the engine harness and people have to replace hardness, ECU, O2 sensor, etc. If the camshaft. If the error has just come up what's the likelihood that the oil has gone far into the harndess?
My plan is to have the mechanic confirm the presence of oil, and if the oil hasn't traveled too far up, change all cam sensors (the newer version of the sensor supposedly has a revised design?) and also add pigtail extensions to isolate the engine harness...
Small:
New plastic sensors are exactly as good as the originals - Good for 20kMiles
The only proven solution is regular replacement of disposable pigtail harness extensions.
Medium:
Hopefully it won't be too bad...
perhaps your issue is a timing issue where the passenger intake CMP wheel has shifted. This causes the sensor to report eroneous data to ECU that detects it as fault.
This happen to engines when ratling is ignored... Ratling actully impacts camshaft and cause loose sensor wheel to shift - MB are carefuly designed to deliver predictible ownership.
Large:
If enough oil has entered the harness, then it's a bit of a ticking time bomb until it messes up the ECU proper.
At that time it will be $10K repair including harness + ECU + sensors replacement.
The sooner things get repaired the cheaper is the tab else things snowball into bigger deals.
