Cam Position Sensor Code
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GL450
Cam Position Sensor Code
2013 GL450 M278 with153k miles. Changed the camshaft sensors at ~142k miles as there was a little oil in three of the four connectors. Original cam adjuster connectors were dry, so I left them. Never any issue with engine performance until...
I yesterday picked up the truck from an oil change at my local indy shop, and around a minute after starting to drive away, the check engine light went on. I turned around and asked them to check the code (after confirming no leaks, oil fill cap on, dipstick in, etc). They called today and said it was a camshaft sensor position code (0340). I told them that they were relatively new, so they checked that the sensors were tight, wire connectors plugged in, reset the code, and took it for three separate test drives. No more code.
Drove 10 miles home without issue, but on second startup was idling roughly. Then was fine on drive.
I find this code a little coincidental immediately after an oil change. Any thoughts appreciated. Thanks.
I yesterday picked up the truck from an oil change at my local indy shop, and around a minute after starting to drive away, the check engine light went on. I turned around and asked them to check the code (after confirming no leaks, oil fill cap on, dipstick in, etc). They called today and said it was a camshaft sensor position code (0340). I told them that they were relatively new, so they checked that the sensors were tight, wire connectors plugged in, reset the code, and took it for three separate test drives. No more code.
Drove 10 miles home without issue, but on second startup was idling roughly. Then was fine on drive.
I find this code a little coincidental immediately after an oil change. Any thoughts appreciated. Thanks.
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2017 GLE350 4MATIC
2013 GL450 M278 with153k miles. Changed the camshaft sensors at ~142k miles as there was a little oil in three of the four connectors. Original cam adjuster connectors were dry, so I left them. Never any issue with engine performance until...
I yesterday picked up the truck from an oil change at my local indy shop, and around a minute after starting to drive away, the check engine light went on. I turned around and asked them to check the code (after confirming no leaks, oil fill cap on, dipstick in, etc). They called today and said it was a camshaft sensor position code (0340). I told them that they were relatively new, so they checked that the sensors were tight, wire connectors plugged in, reset the code, and took it for three separate test drives. No more code.
Drove 10 miles home without issue, but on second startup was idling roughly. Then was fine on drive.
I find this code a little coincidental immediately after an oil change. Any thoughts appreciated. Thanks.
I yesterday picked up the truck from an oil change at my local indy shop, and around a minute after starting to drive away, the check engine light went on. I turned around and asked them to check the code (after confirming no leaks, oil fill cap on, dipstick in, etc). They called today and said it was a camshaft sensor position code (0340). I told them that they were relatively new, so they checked that the sensors were tight, wire connectors plugged in, reset the code, and took it for three separate test drives. No more code.
Drove 10 miles home without issue, but on second startup was idling roughly. Then was fine on drive.
I find this code a little coincidental immediately after an oil change. Any thoughts appreciated. Thanks.
Clean all 10 connectors with CRC contact cleaner. 4xcam sensor, 4xcam magnet and 2xECU
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Joined: Feb 2020
Posts: 126
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From: Gresham, OR
GL450
Some thoughts: It could be the code was pending BEFORE the oil change, and just happened to finally trip the CEL right afterwards. And even now, after being reset, although the CEL is not on the problem may still exist (especially with the rough idle clue). I use the icarsoft MBii scanner to check for more details on my 2013 GL450, or you can use other scanners to tell you if you have a pending code, how many times the error conditions occurred, etc.
Another possibility is you have a wiring/connection issue with the sensors and their cables, and the wiring was "disturbed" during the oil change enough to set the code.
Have you unplugged the sensors and checked to make sure there isn't any residual oil from the original leak in the harness that has migrated back down to the connectors?
Another possibility is you have a wiring/connection issue with the sensors and their cables, and the wiring was "disturbed" during the oil change enough to set the code.
Have you unplugged the sensors and checked to make sure there isn't any residual oil from the original leak in the harness that has migrated back down to the connectors?
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GL450
Makes sense. I’ve never checked the connectors at the ECU. Does anyone know if it’s OK to simply unplug / reconnect the large pin connectors from the ECU? I’m concerned I’ll need to reprogram if I do. (I recall a BMW that required dealer programming to change the battery). Thanks.
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2017 GLE350 4MATIC
Makes sense. I’ve never checked the connectors at the ECU. Does anyone know if it’s OK to simply unplug / reconnect the large pin connectors from the ECU? I’m concerned I’ll need to reprogram if I do. (I recall a BMW that required dealer programming to change the battery). Thanks.
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GL450
Cam sensor and ECU connectors all dry. Engine continues to run normally.
Back to the issue happening immediately after an oil change, could debris entering when refilling the oil possibly impact the sensor? it seems too coincidental to me.
Will monitor and report back.
Back to the issue happening immediately after an oil change, could debris entering when refilling the oil possibly impact the sensor? it seems too coincidental to me.
Will monitor and report back.
Last edited by DTofDUX; Jul 23, 2022 at 10:23 AM.
Out Of Control!!
Joined: Sep 2018
Posts: 14,694
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From: unbegrenzt
2017 GLE350 4MATIC
