Oil leak from rear main seal and/or retainer preventing starting
Thread Starter
Super Member
Joined: Feb 2009
Posts: 692
Likes: 73
From: Houston, TX
2003 E55 AMG; 2013 GL550 4Matic; 2003 CL600
Oil leak from rear main seal and/or retainer preventing starting
Hello,
Since the temperature has started dipping below 60F here in the mornings, I've had a hell of a time with a cold start. After 4-5 cranks it eventually it fires up, sometimes sluggishly, other times very smoothly. Warm starts have been completely normal.
I instantly thought CPS, and swapped it. Same thing. Swapped again, still same thing.
Each time the sensors are coming out covered in oil. I replaced the CPS a few years ago and don't remember it having wet oil on it.
I'm thinking that the constant slow seep from the rear of the motor has gotten worse enough that the cool oil doesn't leak down from the sensor as it did during warmer weather, and this is impeding the functionality of the CPS, in turn causing the bad starts. Strangely I don't see any more oil actually coming out from that area when I look under the car; perhaps its not gushing out, but just slightly worse than before and enough to cause this.
Have any of you experienced this type of failure before? Before I get into the big job of replacing these leaky parts, could anyone offer other alternatives on what could cause bad cold starts?
I've removed a few transmissions at home without a lift and don't want to do it again, especially in RWD where I can't get that area of the body up high, so this will probably be a shop job.
Thanks,
Mike
Since the temperature has started dipping below 60F here in the mornings, I've had a hell of a time with a cold start. After 4-5 cranks it eventually it fires up, sometimes sluggishly, other times very smoothly. Warm starts have been completely normal.
I instantly thought CPS, and swapped it. Same thing. Swapped again, still same thing.
Each time the sensors are coming out covered in oil. I replaced the CPS a few years ago and don't remember it having wet oil on it.
I'm thinking that the constant slow seep from the rear of the motor has gotten worse enough that the cool oil doesn't leak down from the sensor as it did during warmer weather, and this is impeding the functionality of the CPS, in turn causing the bad starts. Strangely I don't see any more oil actually coming out from that area when I look under the car; perhaps its not gushing out, but just slightly worse than before and enough to cause this.
Have any of you experienced this type of failure before? Before I get into the big job of replacing these leaky parts, could anyone offer other alternatives on what could cause bad cold starts?
I've removed a few transmissions at home without a lift and don't want to do it again, especially in RWD where I can't get that area of the body up high, so this will probably be a shop job.
Thanks,
Mike
Senior Member
Joined: Mar 2015
Posts: 386
Likes: 22
From: Tx
04 55
i dont think it would be rear main issue if the cps is covered with oil,,, i would guess valve cover gaskets -- you may want to get a little mirror or inspection camera and look around, you may have other leaks also -- check your battery also
Thread Starter
Super Member
Joined: Feb 2009
Posts: 692
Likes: 73
From: Houston, TX
2003 E55 AMG; 2013 GL550 4Matic; 2003 CL600
The CPS is dry on the outside, at the harness and the bolt. The rest of it is covered in oil, you can only see it by removing it.
I was going to make a video of it this morning, but it started right up. This seems consistent with the theory though, because it sat for 2 days and the oil would've dripped down off the CPS. Or its just confirmation bias.
Member
Joined: Dec 2009
Posts: 168
Likes: 12
2004 E55
Sounds like 1 of 2 issues.
1) does your car make a chirp or squeak during this start up? Does the tip start turn off when this squeak happens? If so try some anti seize applied to the flywheel teeth with a brush through the starter hole or the inspection cover.
2) check your cam position sensor. Right front from driver seat. Cam sensor will cause intermittent no start because it doesn’t know where tdc1 is so it sparks on the wrong phase. This causes it to start every few tries in between a bunch of no starts.
if neither works post pack. The first option is free so try that. Fixed many of them like this.
1) does your car make a chirp or squeak during this start up? Does the tip start turn off when this squeak happens? If so try some anti seize applied to the flywheel teeth with a brush through the starter hole or the inspection cover.
2) check your cam position sensor. Right front from driver seat. Cam sensor will cause intermittent no start because it doesn’t know where tdc1 is so it sparks on the wrong phase. This causes it to start every few tries in between a bunch of no starts.
if neither works post pack. The first option is free so try that. Fixed many of them like this.
Last edited by 210lvr; Nov 22, 2017 at 06:28 PM.
Thread Starter
Super Member
Joined: Feb 2009
Posts: 692
Likes: 73
From: Houston, TX
2003 E55 AMG; 2013 GL550 4Matic; 2003 CL600
Sounds like 1 of 2 issues.
1) does your car make a chirp or squeak during this start up? Does the tip start turn off when this squeak happens? If so try some anti seize applied to the flywheel teeth with a brush through the starter hole or the inspection cover.
2) check your cam position sensor. Right front from driver seat. Cam sensor will cause intermittent no start because it doesn’t know where tdc1 is so it sparks on the wrong phase. This causes it to start every few tries in between a bunch of no starts.
if neither works post pack. The first option is free so try that. Fixed many of them like this.
1) does your car make a chirp or squeak during this start up? Does the tip start turn off when this squeak happens? If so try some anti seize applied to the flywheel teeth with a brush through the starter hole or the inspection cover.
2) check your cam position sensor. Right front from driver seat. Cam sensor will cause intermittent no start because it doesn’t know where tdc1 is so it sparks on the wrong phase. This causes it to start every few tries in between a bunch of no starts.
if neither works post pack. The first option is free so try that. Fixed many of them like this.
1) No chirp or squeak during starting
2) This motor doesn't have a cam position sensor, the cams aren't variable. There is a crankshaft position sensor and I discussed that as a proxy for what I suspect might be the primary issue. I replaced it a few times and it didn't help, each time it came out covered in oil.
The weather got warmer for a while. It is cooling down again so the issue has returned. I'll have some time during the holidays to do cold starts with Star Diagnostics connected, so perhaps I can catch it in the act and get something definitive.
Member
Joined: Dec 2009
Posts: 168
Likes: 12
2004 E55
Thanks for replying,
1) No chirp or squeak during starting
2) This motor doesn't have a cam position sensor, the cams aren't variable. There is a crankshaft position sensor and I discussed that as a proxy for what I suspect might be the primary issue. I replaced it a few times and it didn't help, each time it came out covered in oil.
The weather got warmer for a while. It is cooling down again so the issue has returned. I'll have some time during the holidays to do cold starts with Star Diagnostics connected, so perhaps I can catch it in the act and get something definitive.
1) No chirp or squeak during starting
2) This motor doesn't have a cam position sensor, the cams aren't variable. There is a crankshaft position sensor and I discussed that as a proxy for what I suspect might be the primary issue. I replaced it a few times and it didn't help, each time it came out covered in oil.
The weather got warmer for a while. It is cooling down again so the issue has returned. I'll have some time during the holidays to do cold starts with Star Diagnostics connected, so perhaps I can catch it in the act and get something definitive.
this[img]
http://cdn4.pelicanparts.com/techarticles/Mercedes-W211/59-FUEL-Camshaft_Position_Sensor_Replacement/images_med/pic01.jpg[/img]
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Member
Joined: Dec 2009
Posts: 168
Likes: 12
2004 E55
http://cdn4.pelicanparts.com/techart...arge/pic07.jpg
This engine does not use variable valve timing, it’s not used for that in this application.
This engine does not use variable valve timing, it’s not used for that in this application.
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Thread Starter
Super Member
Joined: Feb 2009
Posts: 692
Likes: 73
From: Houston, TX
2003 E55 AMG; 2013 GL550 4Matic; 2003 CL600
It progressively got worse and eventually would happen with a warm-ish motor, so I tossed out the oil on CPS idea because it barely made sense to begin with and then I just kept seeing contrary info.
Started thinking it might be fuel, especially since I didn't smell near the exhausts any after lots of cranking. Turned out that it was the fuel pump relay! I even had a spare relay of the same part number sitting around.
I always thought a relay would either work or not. Such temperature sensitivity was a surprise to me. I wonder how many other relays will start failing this way and give random outages in cold weather.
Started thinking it might be fuel, especially since I didn't smell near the exhausts any after lots of cranking. Turned out that it was the fuel pump relay! I even had a spare relay of the same part number sitting around.
I always thought a relay would either work or not. Such temperature sensitivity was a surprise to me. I wonder how many other relays will start failing this way and give random outages in cold weather.
MBWorld Fanatic!
Joined: Oct 2015
Posts: 1,811
Likes: 282
From: SC
2005 E55 AMG
It progressively got worse and eventually would happen with a warm-ish motor, so I tossed out the oil on CPS idea because it barely made sense to begin with and then I just kept seeing contrary info.
Started thinking it might be fuel, especially since I didn't smell near the exhausts any after lots of cranking. Turned out that it was the fuel pump relay! I even had a spare relay of the same part number sitting around.
I always thought a relay would either work or not. Such temperature sensitivity was a surprise to me. I wonder how many other relays will start failing this way and give random outages in cold weather.
Started thinking it might be fuel, especially since I didn't smell near the exhausts any after lots of cranking. Turned out that it was the fuel pump relay! I even had a spare relay of the same part number sitting around.
I always thought a relay would either work or not. Such temperature sensitivity was a surprise to me. I wonder how many other relays will start failing this way and give random outages in cold weather.
Checked 2 different times with SDConnect and no codes and fuel pressure was always fine, pump voltage was fine too.
So one day after having every diag tool possible hooked to the car it still was fine. Disconnected everything and was putting tools away and.......BAM IT DID IT FINALLY!
So hooked everything back up, no fuel pressure, checked the pumps and no voltage. Swapped the relay and it is still continuing to start so far. Non starting was so sporadic it's hard to say.
Hopefully that was my issue and yours too!
