P2015, Hard shift 2 to 1, Limp Mode
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From: Allentown, PA
'08 GL 320 CDI
GL320 - P2015, Hard shift 2 to 1, Limp Mode
Yesterday (maybe a little the day before), I started noticing that when coming to a stop, the 2 to 1 downshift was more abrupt/harsh/hard. I figured I would just start paying more attention to things and see how it went. This morning, pulled out from the driveway and within two blocks the CEL lit up and the truck went into limp mode. Continued to work (about 20 minutes) and stopped at an Autozone right next to work and the code was: P2015 Intake manifold runner position sensor/switch circuit range/performance Bank 1. The gentleman at AZ thought the problem was the "Air Charge Temp Sensor". Is this the one that is plugged in directly in front of the turbo, passenger side? I won't get a chance to look at things closer till this evening. I can try clearing the code this evening, too. Being that close to the turbo (if this IS the location), I wouldn't be surprised if it's been bathing in oil mist!
In the meantime, any thoughts? I tried to do some research and come up with issues surrounding the "flapper valves" and a plastic connecting rod... but not sure if that is proper research or even if I'm using the right terms. I've tested temp sensors in a pot of water, on the stove - watching the resistance go lower as the water heats up. Is there any reason I can't do that with this sensor? Assuming, it the one right there at the turbo which is easy to get to, of course.
I do have a warranty through the place I bought this car from, although they're a little inconvenient to get to - but they're a good place. If it's a relatively easy/inexpensive fix, though, I'd just do it myself.
In the meantime, any thoughts? I tried to do some research and come up with issues surrounding the "flapper valves" and a plastic connecting rod... but not sure if that is proper research or even if I'm using the right terms. I've tested temp sensors in a pot of water, on the stove - watching the resistance go lower as the water heats up. Is there any reason I can't do that with this sensor? Assuming, it the one right there at the turbo which is easy to get to, of course.
I do have a warranty through the place I bought this car from, although they're a little inconvenient to get to - but they're a good place. If it's a relatively easy/inexpensive fix, though, I'd just do it myself.
Last edited by DennisG01; Feb 27, 2019 at 09:09 PM.
Thread Starter
MBWorld Fanatic!
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From: Allentown, PA
'08 GL 320 CDI
It looks like the sensor I was thinking of (passenger side of turbo, up top on the engine where it would be nice and easy to get to) is not the right one. That one might be a MAF? But it is definitely not the one I'm looking for.
I tried to read the codes with my scanner when I got home, just to double check, but it didn't read them properly. It did allow me to clear the code. But the limp mode remains, even though the CEL light is not "on", anymore.
I tried to read the codes with my scanner when I got home, just to double check, but it didn't read them properly. It did allow me to clear the code. But the limp mode remains, even though the CEL light is not "on", anymore.
Thread Starter
MBWorld Fanatic!
Joined: May 2015
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From: Allentown, PA
'08 GL 320 CDI
CEL light came back on this morning as I left the neighborhood - within about 3 or 4 minutes of driving.
(Noting this primarily for documentation reasons, in case anyone in the future has a similar issue)
(Noting this primarily for documentation reasons, in case anyone in the future has a similar issue)
Thread Starter
MBWorld Fanatic!
Joined: May 2015
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From: Allentown, PA
'08 GL 320 CDI
Thanks, Alex. If I'm understanding correctly, Star/DAS goes into more details... reads more/further into the system?
Seeing as how it appears to be a more involved fix than just a little sensor mounted right up top, I made an appointment to talk with the mechanic I've been using. Since I have the warranty, I suppose I should use it! I will definitely post back with info.
Seeing as how it appears to be a more involved fix than just a little sensor mounted right up top, I made an appointment to talk with the mechanic I've been using. Since I have the warranty, I suppose I should use it! I will definitely post back with info.
Thread Starter
MBWorld Fanatic!
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From: Allentown, PA
'08 GL 320 CDI
Back with more info - sorry for the delay - the shop was overloaded with work so it took a while for them to get to it. I talked with the tech today and he said the issue is with the intake manifold "butterfly valves". He confirmed that the Intake Runner Position Switch was the only code in there. The hole in the arm that controls them (it's a plastic piece) has gotten oblong in shape (he used the term 'egged out'... which makes sense) and the butterfly valves are not doing what they should, when they should.
Unfortunately, this is not covered under the warranty I have. Also, unfortunately, I don't have much spare time right now to tackle this myself and it sounds like this is full day job for someone that's done it before... longer for me! The tech mentioned that according to MB, the only way to fix this is an entire intake manifold from MB since the parts aren't available separately through MB. However, he did some extra research and it seems as though there are aftermarket kits available (in metal) for this. I said I'd do some homework on that... which leads me back to here! I'll start googling for this, but does anyone have any more information to offer that would help?
Alex, forgive me - I assume you probably already know everything I was saying in this post! I'm really just trying to explain it so there is record of it for future use.
EDIT: I found this: https://www.ebay.com/i/183716367652?...3D183716367652
Unfortunately, this is not covered under the warranty I have. Also, unfortunately, I don't have much spare time right now to tackle this myself and it sounds like this is full day job for someone that's done it before... longer for me! The tech mentioned that according to MB, the only way to fix this is an entire intake manifold from MB since the parts aren't available separately through MB. However, he did some extra research and it seems as though there are aftermarket kits available (in metal) for this. I said I'd do some homework on that... which leads me back to here! I'll start googling for this, but does anyone have any more information to offer that would help?
Alex, forgive me - I assume you probably already know everything I was saying in this post! I'm really just trying to explain it so there is record of it for future use.
EDIT: I found this: https://www.ebay.com/i/183716367652?...3D183716367652
Last edited by DennisG01; Mar 21, 2019 at 06:18 PM.
