'15 C300 stalls on startup and accelerate issues P033900 and P033904 - faulty CPS?
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C300 W205
'15 C300 stalls on startup and accelerate issues P033900 and P033904 - faulty CPS?
Hi. I am having a problem with my 2015 Mercedes C300 W205. A few days ago, I've noticed that it stalled on startupz twice happened twice. Another, most likely related, issue is that it often does not want to accelerate, the RPM won't exceed 2000 and it takes 15s to reach 40mph. I also noticed small sporadic jerks while driving. This only happens sometimes and when I turn the engine off and on, it usually comes back to normal. No lights or issues showing on the dashboard. I checked the car with a scanner and it it throwing these errors: P033900 - Position sensor 1 for the crankshaft has a sporadic malfunction. P033904 - Position sensor 1 for the crankshaft has a sporadic malfunction.There is an internal fault. P06DA00 - The actuation of the valve of the oil pump in the combustion engine has an electrical fault or open circuit. Could this be the crankshaft position sensor? If so, am I fine with an aftermarket sensor or should I do with OEM/Genuine? Does it make a difference with these sensors? I need to fix it asap so I would prefer to get an aftermarket from Amazon. Additionally, there's the oil pump error but I'll address this later, unless it's an easy fix while replacing the CPS
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W212 MY'14 M276-3.5NA @75kMi
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Hi. I am having a problem with my 2015 Mercedes C300 W205. A few days ago, I've noticed that it stalled on startupz twice happened twice. Another, most likely related, issue is that it often does not want to accelerate, the RPM won't exceed 2000 and it takes 15s to reach 40mph. I also noticed small sporadic jerks while driving. This only happens sometimes and when I turn the engine off and on, it usually comes back to normal. No lights or issues showing on the dashboard. I checked the car with a scanner and it it throwing these errors: P033900 - Position sensor 1 for the crankshaft has a sporadic malfunction. P033904 - Position sensor 1 for the crankshaft has a sporadic malfunction.There is an internal fault. P06DA00 - The actuation of the valve of the oil pump in the combustion engine has an electrical fault or open circuit. Could this be the crankshaft position sensor? If so, am I fine with an aftermarket sensor or should I do with OEM/Genuine? Does it make a difference with these sensors? I need to fix it asap so I would prefer to get an aftermarket from Amazon. Additionally, there's the oil pump error but I'll address this later, unless it's an easy fix while replacing the CPS
- 1- Your CAM Position Sensor(s) have failed
- 2- You oil pump solenoid has failed electrically
1- Roasted Cam sensors:
-- Inspect/replace intake + exhaust $50Ea. CPS for oil in connector.
-- Add a sacrificial pigtail extension to help preserve you from "$10k-oil-in-harness".
2-Pump solenoid :
This one can be an expensive but some ppl see it as a unnecessary item... a "Lucky fault" that can help lubricate the engine pistons with better pressure under 3000Rpm.
3-Extreme heatsoaks:
Use better oil than stock for shorter distance than recommended interval.
Such as a Motul 5w40 for 4kMi.
Last edited by CaliBenzDriver; Jan 31, 2025 at 02:11 PM.
Thread Starter
Junior Member
Joined: Mar 2021
Posts: 29
Likes: 1
C300 W205
Thank you.
So you think that it's the camshaft position sensor, not the crankshaft position sensor?
I ordered the crankshaft position sensor, which got delivered today and was planning on replacing it.
I'm using 5w30 oil. That's what was recommended by Mercedes in Florida climate. I only use the car for short distances. This issue started after the car was sitting for 2 weeks.
So you think that it's the camshaft position sensor, not the crankshaft position sensor?
I ordered the crankshaft position sensor, which got delivered today and was planning on replacing it.
I'm using 5w30 oil. That's what was recommended by Mercedes in Florida climate. I only use the car for short distances. This issue started after the car was sitting for 2 weeks.
