turbo cuts out...
01-05-2017, 04:32 PM
#26
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GL 320, 993TT, BMW 550XI
Originally Posted by thetonka
So I don't have the time right now to work on my R. I took it to a local shop and they found a cracked exhaust manifold. They found a TSB for this and talked to Mercedes.
Mercedes is telling them that both manifolds need to be replaced, only one is obviously cracked, and the turbo needs to be replaced. They are saying the turbo is slowing down and causing too much heat that results in cracks.
I'm not buying it. That doesn't make sense unless the turbo is a bad design, or the exhaust manifolds are cheap and crappy. Either way replacing them with the same thing will just result in the same problem.
I am having them replace the cracked manifold. If I need to replace the turbo I can do that. This car has 125,000 miles on it. If I can get another 80,000 I will be happy.
I am going to post this in another post for more comments.
Mercedes is telling them that both manifolds need to be replaced, only one is obviously cracked, and the turbo needs to be replaced. They are saying the turbo is slowing down and causing too much heat that results in cracks.
I'm not buying it. That doesn't make sense unless the turbo is a bad design, or the exhaust manifolds are cheap and crappy. Either way replacing them with the same thing will just result in the same problem.
I am having them replace the cracked manifold. If I need to replace the turbo I can do that. This car has 125,000 miles on it. If I can get another 80,000 I will be happy.
I am going to post this in another post for more comments.
01-05-2017, 07:35 PM
#27
Member
Good to know it is the same. I usually will do work like this myself but my job has me traveling a lot so I don't have that option. Sometimes you just have to pay the price and get it done.
Last edited by thetonka; 01-06-2017 at 08:52 PM.
04-01-2017, 01:33 PM
#28
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2008 GL320 CDI
Turbo Limp Mode when GL320 is HOT - FIXED
I have an '08 GL320 cdi with 145,000 miles.
I experienced the following issue with Turbo going into limp mode after restarting an up to operating temperature GL320.
1. When starting 'cold' (I live in FL so it's relative) or not at operating temp, the vehicle and turbo performed great. Once going, up to speed, and at normal operating temperature, the vehicle continued to run fine, with normal turbo boost.
2. After a drive where vehicle was able to get to normal operating temperature and then stopped for a few minutes and turned OFF, the car would then respond by going into limp mode when restarted, with NO Turbo boost. The vehicle would accelerate, but very slowly with NO Turbo.
3. Only after the vehicle was allowed to sit and cool down (engine off) for at least an hour, would the situation return to number 1 above.
The check engine light was on, so I went to Advanced Autoparts and they scanned the codes for free. The OBD code reader showed code P1400 Manifold Differential Pressure Sensor Circuit Malfunction - voila!
Note I went to Advanced (above) for the code reader, after I had read a number of threads, and one indicated the Differential Pressure Sensor had fixed a similar problem. So, I went to the MB $tealership and purchased part A 642 905 01 00 (pressure sensor). The dealer charged me $82 for the part...b/c they thought I was a rep. The retail price at the dealer is about $140. I saw the same part by Bosch online for around $30 plus shipping, but I couldn't wait for it to arrive.
The install would have been a snap, except I didn't have the correct tool (go figure) to uninstall the two hoses that feed the sensor. I attached a file to this thread that shows the location of the sensor. I struggled for a couple hours to uninstall the screwless hose clamps, but was finally able to do so without damaging anything. I would highly recommend that you buy the tool for this in advance and avoid lying underneath your car jacks for the hours that I did.....or take it to an Indy that has the tool and a lift.
If you have the tool, this job should take you around an hour. There is only one nut (8 or 10mm) that is easily accessed, and if you have the right tool, the screwless hose clamps should be a chip shot. Due to time issues, I purchased standard screw type hose clamps for my reinstall, and while they are bulky, they were easy to install.
I've only driven the vehicle for a day, but after a few test runs where I would get the vehicle up to operating temp., turning it off, and then restarting while still 'hot', the Turbo has worked as intended. WooHoo! In addition, the Engine Check Light is now OFF (this took about 5 restarts if I recall correctly).
If I don't post again, then make the assumption that this fix was a good one. Good luck, and remember to share your experiences after you solve a problem so others can learn from your experience!
All the best,
Flying Fish
your real estate expert in the upper florida keys
305 807 4858
I experienced the following issue with Turbo going into limp mode after restarting an up to operating temperature GL320.
1. When starting 'cold' (I live in FL so it's relative) or not at operating temp, the vehicle and turbo performed great. Once going, up to speed, and at normal operating temperature, the vehicle continued to run fine, with normal turbo boost.
2. After a drive where vehicle was able to get to normal operating temperature and then stopped for a few minutes and turned OFF, the car would then respond by going into limp mode when restarted, with NO Turbo boost. The vehicle would accelerate, but very slowly with NO Turbo.
3. Only after the vehicle was allowed to sit and cool down (engine off) for at least an hour, would the situation return to number 1 above.
The check engine light was on, so I went to Advanced Autoparts and they scanned the codes for free. The OBD code reader showed code P1400 Manifold Differential Pressure Sensor Circuit Malfunction - voila!
Note I went to Advanced (above) for the code reader, after I had read a number of threads, and one indicated the Differential Pressure Sensor had fixed a similar problem. So, I went to the MB $tealership and purchased part A 642 905 01 00 (pressure sensor). The dealer charged me $82 for the part...b/c they thought I was a rep. The retail price at the dealer is about $140. I saw the same part by Bosch online for around $30 plus shipping, but I couldn't wait for it to arrive.
The install would have been a snap, except I didn't have the correct tool (go figure) to uninstall the two hoses that feed the sensor. I attached a file to this thread that shows the location of the sensor. I struggled for a couple hours to uninstall the screwless hose clamps, but was finally able to do so without damaging anything. I would highly recommend that you buy the tool for this in advance and avoid lying underneath your car jacks for the hours that I did.....or take it to an Indy that has the tool and a lift.
If you have the tool, this job should take you around an hour. There is only one nut (8 or 10mm) that is easily accessed, and if you have the right tool, the screwless hose clamps should be a chip shot. Due to time issues, I purchased standard screw type hose clamps for my reinstall, and while they are bulky, they were easy to install.
I've only driven the vehicle for a day, but after a few test runs where I would get the vehicle up to operating temp., turning it off, and then restarting while still 'hot', the Turbo has worked as intended. WooHoo! In addition, the Engine Check Light is now OFF (this took about 5 restarts if I recall correctly).
If I don't post again, then make the assumption that this fix was a good one. Good luck, and remember to share your experiences after you solve a problem so others can learn from your experience!
All the best,
Flying Fish
your real estate expert in the upper florida keys
305 807 4858
