07 GL450 Misfiring Issue. Please Help!
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Newbie
Joined: Mar 2018
Posts: 14
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07 GL450
07 GL450 Misfiring Issue. Please Help!
So last November, I installed a new intake manifold, along with brand new ignition coils and spark plugs. Three weeks ago, my truck started misfiring badly. I managed to change both sets of plugs and coils (lifetime warranty). The truck ran fine for about a week then I ran into the same problem again. Yesterday, I received another set of plugs and discovered that the plugs from cylinder 3, 4, 6, and 7 were burnt out. Along with changing all the plugs, I also changed the air filters because I believe that was the culprit (they were filthy). The truck somewhat ran better, but still misfired. Today, I purchased an OBD2 scanner (I know, that should've been the first step). At first, the code that appeared was P0307 (Cylinder 7 misfire). I tried clearing the code and now I'm receiving the codes P0303, P0304, P0305, P0306, P0307, and P0308. What could now be the problem?! Should I change the coils as well?
Also, quick question. I told a mechanic about my situation and he told me that the plugs are definitely the problem because the plugs I purchased from eBay, which are branded as OEM (MB/Bosch) are basically replicas and that I should purchase from MB directly. Is there any truth to this? Could this be the issue with the coils as well? Because, the one's I purchased aren't name brand and I shouldn't be having the same issue within less than a year.
Any help or advice would be appreciated,
Also, quick question. I told a mechanic about my situation and he told me that the plugs are definitely the problem because the plugs I purchased from eBay, which are branded as OEM (MB/Bosch) are basically replicas and that I should purchase from MB directly. Is there any truth to this? Could this be the issue with the coils as well? Because, the one's I purchased aren't name brand and I shouldn't be having the same issue within less than a year.
Any help or advice would be appreciated,
Out Of Control!!
Joined: Sep 2018
Posts: 14,666
Likes: 4,568
From: unbegrenzt
2017 GLE350 4MATIC
Repeated misfire with known good plugs and coils means another problem is at hand.
Read codes. Eliminate all other easy to address problems such as filters, oil change, clean the engine bay, etc. This procedure will lead you to the problem.
Bad sensor somewhere is likely.
Read codes. Eliminate all other easy to address problems such as filters, oil change, clean the engine bay, etc. This procedure will lead you to the problem.
Bad sensor somewhere is likely.
Thread Starter
Newbie
Joined: Mar 2018
Posts: 14
Likes: 2
07 GL450
Repeated misfire with known good plugs and coils means another problem is at hand.
Read codes. Eliminate all other easy to address problems such as filters, oil change, clean the engine bay, etc. This procedure will lead you to the problem.
Bad sensor somewhere is likely.
Read codes. Eliminate all other easy to address problems such as filters, oil change, clean the engine bay, etc. This procedure will lead you to the problem.
Bad sensor somewhere is likely.
Member
Joined: Aug 2014
Posts: 88
Likes: 8
2011 GL450 VIN: 4JGBF7BE8BA706134
Interesting, b/c I’m also receiving codes P0016 and P0017 along with the other codes. Months before changing the intake manifold, my mechanic told me about the camshaft sensor was also bad, but told me that there was nothing to worry about. Quick question. Can the camshaft sensor also play a role w/ starting the engine? For the past two days, the truck hesistates to start at first; however, If I turn the ignition off and back on, it starts normally.
You likely have the balance shaft problem that is notorious with those particular engine models. My 2006 ML350 had it. You can confirm this by doing this test.
Follow these steps to confirm:
You will remove the 2 left camshaft position sensors, turn the crankshaft to 305 degrees (you might have to go around a full turn for this to work) and you will see 2 emblems inside the holes. If they are dead center...you are fine and it's likely a sensor issue. If they are off center, you are screwed.
The balance shaft is off, and will only get worse..which involves the timing chain, teeth getting sheered off slowly, etc.. and the only fix is to get the inside rebuilt. My terminology is off on this, but it will be at minimum a $1500-2000 fix and could be $4,000.
Newbie
Joined: Jun 2019
Posts: 11
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GL 450
Originally Posted by jemison60 
Im having shifting problems occasionally when accelerating out of a near stop, usually cornering'
The acceleration feels of occasion like being bumped from behind.
I take the car to two German auto certified shops and for the last week its been at the local dealer.
All information and diagnosis states no transmission problems'
Only Intake Manifold and vacuum leaks
CEL on DTC Test 2092, 2096
one shop also added crankcase vent valve and oil filter housing and oil cooler seals
No fault or stored transmission codes.
I would appreciate any advice, runs great otherwise and shifts smoothly
Im having shifting problems occasionally when accelerating out of a near stop, usually cornering'
The acceleration feels of occasion like being bumped from behind.
I take the car to two German auto certified shops and for the last week its been at the local dealer.
All information and diagnosis states no transmission problems'
Only Intake Manifold and vacuum leaks
CEL on DTC Test 2092, 2096
one shop also added crankcase vent valve and oil filter housing and oil cooler seals
No fault or stored transmission codes.
I would appreciate any advice, runs great otherwise and shifts smoothly
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