Bad temp sensor
MBWorld Fanatic!
Joined: Aug 2010
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MB
WELP the new sensor seemed to stabilize things a bit (not completely tho), especially once I reach the 177F mark HOWEVER I just returned from lunch and my digital display wasn't reading the oil temp AT ALL, it just showed --- !
When I turned the car off after the 2 minute drive back to the office for lunch the fans stayed on long after the car was off (which considering its a nice 88 degrees outside today and it never did that when it was 110 out is concerning to me). Looks like I'll be heading back to the dealer and most likely switching to a different dealership all together, my impressions of my current dealer keep getting lower.
When I turned the car off after the 2 minute drive back to the office for lunch the fans stayed on long after the car was off (which considering its a nice 88 degrees outside today and it never did that when it was 110 out is concerning to me). Looks like I'll be heading back to the dealer and most likely switching to a different dealership all together, my impressions of my current dealer keep getting lower.
Junior Member
Joined: Apr 2011
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FIXED!
Okay so after leaving the car at the dealer for another 4 days, the problem has been fixed! Here's what the official writeup from the dealership states:
"Pin loose for engine oil temperature sensor at plug on engine control unit, causing sporadic reading in instrument cluster. Perform short test (54-1011), code 3719 oil temp sensor implausible; check resistance of wiring going to sensor pin 82 at ECU and pin 2 at sensor resistance at .3ohms, check pin tension at engine control unit and found very loose compared to other pins, replaced pin 82 in engine control harness (1.9)."
The temp is definitely more stable and consistent than ever before. I'll keep an eye on it but as of right now, I'd say it's fixed!
"Pin loose for engine oil temperature sensor at plug on engine control unit, causing sporadic reading in instrument cluster. Perform short test (54-1011), code 3719 oil temp sensor implausible; check resistance of wiring going to sensor pin 82 at ECU and pin 2 at sensor resistance at .3ohms, check pin tension at engine control unit and found very loose compared to other pins, replaced pin 82 in engine control harness (1.9)."
The temp is definitely more stable and consistent than ever before. I'll keep an eye on it but as of right now, I'd say it's fixed!
Junior Member
Joined: Apr 2011
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EDIT: The only quirk I notice is that I'll be cruising along @ 80 MPH oil temp will be around 210 and if I start to really push the car the oil temp will drop to 150-170, it's almost as if the fan kicks in and really works to cool the oil. Who knows, but I'd still say the problem is solved.
MBWorld Fanatic!
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MB
EDIT: The only quirk I notice is that I'll be cruising along @ 80 MPH oil temp will be around 210 and if I start to really push the car the oil temp will drop to 150-170, it's almost as if the fan kicks in and really works to cool the oil. Who knows, but I'd still say the problem is solved.
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Joined: Jul 2008
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From: Massachusetts
'14 911S (garage queen) '13 X3 (family hauler)
This is just crazy!
How can AMG build a car with such a crappy oil temp sensor?
I just had my service A done and I thought I noticed my oil temp acting weird after the oil change.
Mine hasn't dropped down in temp, but it seems to run hotter than before (even during this cooler weather). I haven't driven the car much since getting the service done, but as soon as I get home from vacation I'll give it a better test run. My wife and kids want to stay another night, so much for getting home today and watching football!
Could our oil temp sensors get damaged from oil changes? Siphon line hitting it, etc.
Not sure where the sensor is--anyone know?
How can AMG build a car with such a crappy oil temp sensor?
I just had my service A done and I thought I noticed my oil temp acting weird after the oil change.
Mine hasn't dropped down in temp, but it seems to run hotter than before (even during this cooler weather). I haven't driven the car much since getting the service done, but as soon as I get home from vacation I'll give it a better test run. My wife and kids want to stay another night, so much for getting home today and watching football!
Could our oil temp sensors get damaged from oil changes? Siphon line hitting it, etc.
Not sure where the sensor is--anyone know?
MBWorld Fanatic!
Joined: Aug 2010
Posts: 2,493
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MB
Okay so after leaving the car at the dealer for another 4 days, the problem has been fixed! Here's what the official writeup from the dealership states:
"Pin loose for engine oil temperature sensor at plug on engine control unit, causing sporadic reading in instrument cluster. Perform short test (54-1011), code 3719 oil temp sensor implausible; check resistance of wiring going to sensor pin 82 at ECU and pin 2 at sensor resistance at .3ohms, check pin tension at engine control unit and found very loose compared to other pins, replaced pin 82 in engine control harness (1.9)."
The temp is definitely more stable and consistent than ever before. I'll keep an eye on it but as of right now, I'd say it's fixed!
"Pin loose for engine oil temperature sensor at plug on engine control unit, causing sporadic reading in instrument cluster. Perform short test (54-1011), code 3719 oil temp sensor implausible; check resistance of wiring going to sensor pin 82 at ECU and pin 2 at sensor resistance at .3ohms, check pin tension at engine control unit and found very loose compared to other pins, replaced pin 82 in engine control harness (1.9)."
The temp is definitely more stable and consistent than ever before. I'll keep an eye on it but as of right now, I'd say it's fixed!
So far, my dealership is taking a firm stance that the issue is normal and they have no way to fix it. The service managaer "says" he will be contacting someone tomorrow to learn more about this issue.
Also, my car got an oil change today and now when I accelerate there is a really annoying fluttering sound that you can hear from the engine. It has completely changed the sound of the exhaust in my car's cabin.
I'll update when I find out more info on the oil temp digital display.
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Junior Member
Joined: Aug 2016
Posts: 41
Likes: 3
Bmw m5 , c63
Okay so after leaving the car at the dealer for another 4 days, the problem has been fixed! Here's what the official writeup from the dealership states:
"Pin loose for engine oil temperature sensor at plug on engine control unit, causing sporadic reading in instrument cluster. Perform short test (54-1011), code 3719 oil temp sensor implausible; check resistance of wiring going to sensor pin 82 at ECU and pin 2 at sensor resistance at .3ohms, check pin tension at engine control unit and found very loose compared to other pins, replaced pin 82 in engine control harness (1.9)."
The temp is definitely more stable and consistent than ever before. I'll keep an eye on it but as of right now, I'd say it's fixed!
"Pin loose for engine oil temperature sensor at plug on engine control unit, causing sporadic reading in instrument cluster. Perform short test (54-1011), code 3719 oil temp sensor implausible; check resistance of wiring going to sensor pin 82 at ECU and pin 2 at sensor resistance at .3ohms, check pin tension at engine control unit and found very loose compared to other pins, replaced pin 82 in engine control harness (1.9)."
The temp is definitely more stable and consistent than ever before. I'll keep an eye on it but as of right now, I'd say it's fixed!
So it's just a loose pin ?
MBWorld Fanatic!
Joined: Jun 2008
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From: Los Angeles
2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
Member
Joined: Mar 2013
Posts: 98
Likes: 2
From: Chicago, IL
2010 C63
So how frequently do our oil temp sensors give? I don't know - it just seems like a strange wear item to me.
Mine went completely silent on me this morning on my hour drive in to work. The sensor seemed to be working when I started the car..then about 20 minutes into the drive, it went blank showing "---F" on my gauge. The coolant temp right underneath was showing up fine. I got to work, parked it, turned off the car, then back on, and it still showed no reading. I turned off the car, got out, and the fan kept running for about a minute and shut off on its own.
Fast forward 3.5 hours, and it was reading out the temp again. About 40 minutes of driving later however, I noticed the engine oil was reading about 150F ish quite consistently and not fluctuating. Even on cooler days, after that much constant driving, the readings would normally be at 200F ish. Is my temp sensor a goner?
Mine went completely silent on me this morning on my hour drive in to work. The sensor seemed to be working when I started the car..then about 20 minutes into the drive, it went blank showing "---F" on my gauge. The coolant temp right underneath was showing up fine. I got to work, parked it, turned off the car, then back on, and it still showed no reading. I turned off the car, got out, and the fan kept running for about a minute and shut off on its own.
Fast forward 3.5 hours, and it was reading out the temp again. About 40 minutes of driving later however, I noticed the engine oil was reading about 150F ish quite consistently and not fluctuating. Even on cooler days, after that much constant driving, the readings would normally be at 200F ish. Is my temp sensor a goner?
Newbie
Joined: Apr 2016
Posts: 1
Likes: 0
From: Stockholm
C63 w204
have you found the problem
have you found the problem? I have the same issue. Have done the same thing changing the oil temp sensors and the hole ecu box. Still have the problem. I know this is and old tread but can’t find the answer anywhere. Sorry for my bad English.
MBWorld Fanatic!
Joined: Nov 2012
Posts: 2,768
Likes: 419
'10 C63
My car recently started doing the same thing. The oil temp would go DOWN below normal operating temp when on the throttle, even after hours of driving. I replaced the sensor with no change. I figured I would try to sort it later. In the meantime, I replaced all my injectors. What do you know? It fixed it! Oil temp now warms up steadily and stays around 206F on the freeway. No more jumping around or anything. It’s a 2010 with 100k miles and had Q4 injectors. I got new ones from RM European for $21 each. The car is so alive now and gets better mpg. I’m so happy I killed 2 birds with one fairly inexpensive stone. Not sure what would cause this but that’s what fixed the oil temp reading for me
Newbie
Joined: Aug 2015
Posts: 10
Likes: 2
P31 C63 AMG
My car recently started doing the same thing. The oil temp would go DOWN below normal operating temp when on the throttle, even after hours of driving. I replaced the sensor with no change. I figured I would try to sort it later. In the meantime, I replaced all my injectors. What do you know? It fixed it! Oil temp now warms up steadily and stays around 206F on the freeway. No more jumping around or anything. It’s a 2010 with 100k miles and had Q4 injectors. I got new ones from RM European for $21 each. The car is so alive now and gets better mpg. I’m so happy I killed 2 birds with one fairly inexpensive stone. Not sure what would cause this but that’s what fixed the oil temp reading for me
MBWorld Fanatic!
Joined: Nov 2012
Posts: 2,768
Likes: 419
'10 C63
Man. These leaky injectors must be making the motors run cool or are somehow letting cool fuel skew the oil temp reading. I changed my oil and it didn’t smell like fuel. I didn’t do an oil analysis so I don’t know if fuel was contaminating the oil. At least this is a relatively cheap and easy fix.
