2015 C300 misfiring cylinder 3
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C300
2015 C300 misfiring cylinder 3
starting with a P0016 timing issue. I changed the solenoids, camshaft sensor with one mechanic. camshaft gears, the intake camshaft itself changed last week. After having the vehicle for three weeks I picked it up on July 21 and drove it for 15 miles home. Car stalled and check engine light returned. Contacted mechanic who towed it back to his shop after running a new diagnostic I now had a P2118 code. Mechanic recommended changing the crank case, ventilation valve assembly. The following is the new finding:
Cleared codes and road tested after repairs. After car heats up, can feel car misfiring. Ran quick test and have current codes for misfire in cylinder #3. Swapped ignition coils for cyl 2 and 3. Ran engine. Misfire does not move. Swapped spark plugs cyl 2 and 3. Ran engine misfire does not move. Need testing time to go further with the car to resolve misfire. Note that this car has had what seems to be poor workmanship in the past (repair wise) as indicated by what we have been seeing as repairs have been made to the engine (loose bolts, missing bolts, poor installation of components etc..)
I am having my car towed home tomorrow. Any suggestions on this fix will be greatly appreciate it.
Cleared codes and road tested after repairs. After car heats up, can feel car misfiring. Ran quick test and have current codes for misfire in cylinder #3. Swapped ignition coils for cyl 2 and 3. Ran engine. Misfire does not move. Swapped spark plugs cyl 2 and 3. Ran engine misfire does not move. Need testing time to go further with the car to resolve misfire. Note that this car has had what seems to be poor workmanship in the past (repair wise) as indicated by what we have been seeing as repairs have been made to the engine (loose bolts, missing bolts, poor installation of components etc..)
I am having my car towed home tomorrow. Any suggestions on this fix will be greatly appreciate it.
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2009 MB C300 Sport 4matic
Was a decent Mercedes Dealer involved here ? A STAR diagnostic with real time freeze frame read outs seems to be needed to decipher the various reasons for the rich mixture code..
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C300
yes. But this mechanic shop diagnostic is broken into tier levels so the 3rd one was costing me $450. Hence why I’m picking it up. Certified Mercedes master technician . 1st diagnosis was for the gears and camshaft replacement, 2nd was free for the returned vehicle.
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2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Have you considered a bad fuel injector or wiring? How many miles are on the car? Any consumption of coolant? Have you done a compression test of cylinder 3? A leak-down test?
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C300
The vehicle had 77805. No coolant consumption. Other test not done yet. Towing it to a dealership next week. Also I DO need a battery. Could that cause the misfire?
Joined: Nov 2016
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From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
I doubt the battery would cause this, though these cars do seem to be very temperamental when it comes to battery health. They also require precise torquing of the spark plugs -- no tightening by feel.
Remember, proper ignition requires the right mix of fuel, air, spark and compression. Misfires are determined by the amount of unburnt fuel in the exhaust at a specific moment and is assigned to the cylinder that the ECU detects should have fired correctly. So, if you are getting a P2188 code (lean condition has been detected on bank 1 of the engine during idle) and misfires on cylinder 3 (should be a P0303 DTC), you may have a significant air leak. Did you also get a P0303 code or how did you determine cylinder 3 was misfiring?
Remember, proper ignition requires the right mix of fuel, air, spark and compression. Misfires are determined by the amount of unburnt fuel in the exhaust at a specific moment and is assigned to the cylinder that the ECU detects should have fired correctly. So, if you are getting a P2188 code (lean condition has been detected on bank 1 of the engine during idle) and misfires on cylinder 3 (should be a P0303 DTC), you may have a significant air leak. Did you also get a P0303 code or how did you determine cylinder 3 was misfiring?
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C300
I doubt the battery would cause this, though these cars do seem to be very temperamental when it comes to battery health. They also require precise torquing of the spark plugs -- no tightening by feel.
Remember, proper ignition requires the right mix of fuel, air, spark and compression. Misfires are determined by the amount of unburnt fuel in the exhaust at a specific moment and is assigned to the cylinder that the ECU detects should have fired correctly. So, if you are getting a P2188 code (lean condition has been detected on bank 1 of the engine during idle) and misfires on cylinder 3 (should be a P0303 DTC), you may have a significant air leak. Did you also get a P0303 code or how did you determine cylinder 3 was misfiring?
Remember, proper ignition requires the right mix of fuel, air, spark and compression. Misfires are determined by the amount of unburnt fuel in the exhaust at a specific moment and is assigned to the cylinder that the ECU detects should have fired correctly. So, if you are getting a P2188 code (lean condition has been detected on bank 1 of the engine during idle) and misfires on cylinder 3 (should be a P0303 DTC), you may have a significant air leak. Did you also get a P0303 code or how did you determine cylinder 3 was misfiring?
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Out Of Control!!
Joined: Sep 2018
Posts: 14,666
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From: unbegrenzt
2017 GLE350 4MATIC
Throw parts at this car with abandon, it’s what I would do:
New coils
new plugs
crank posn sensor
new battery
And for good measure all new pcv and purge components in the engine bay
Then report back. None of these parts are individually expensive and none of the labor is difficult.
New coils
new plugs
crank posn sensor
new battery
And for good measure all new pcv and purge components in the engine bay
Then report back. None of these parts are individually expensive and none of the labor is difficult.
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C300
Throw parts at this car with abandon, it’s what I would do:
New coils
new plugs
crank posn sensor
new battery
And for good measure all new pcv and purge components in the engine bay
Then report back. None of these parts are individually expensive and none of the labor is difficult.
New coils
new plugs
crank posn sensor
new battery
And for good measure all new pcv and purge components in the engine bay
Then report back. None of these parts are individually expensive and none of the labor is difficult.
Last edited by KenBad74; Jul 27, 2023 at 11:25 AM. Reason: spelling
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C300
Sorry
i sent a picture of the mechanics notes. It reads:
Cleared codes and road tested after repairs. After car heats up,can feel car misfiring. Ran quick test and HAVE CURRENT CODES FOR MIFIRE IN CYLINDER 3. Swapped ignition coils for cyl 2 and 3. Ran engine. Misfire does not move. Swapped spark plugs for cyl 2 and 3. Ran engine. Misfire does not move. Need testting time to go further with the car to resolve imisfire.($450) Note- This car had whatseems to be poor workmanship in the past (repair wise) as indicated by what we have been seeing as repairs have been made to the engine(loose bolts,missing bolts,poor installation of components etc)
I ahve only own the vehicle for 2 yers and bought it at 65K. Currently at 77K.
i sent a picture of the mechanics notes. It reads:
Cleared codes and road tested after repairs. After car heats up,can feel car misfiring. Ran quick test and HAVE CURRENT CODES FOR MIFIRE IN CYLINDER 3. Swapped ignition coils for cyl 2 and 3. Ran engine. Misfire does not move. Swapped spark plugs for cyl 2 and 3. Ran engine. Misfire does not move. Need testting time to go further with the car to resolve imisfire.($450) Note- This car had whatseems to be poor workmanship in the past (repair wise) as indicated by what we have been seeing as repairs have been made to the engine(loose bolts,missing bolts,poor installation of components etc)
I ahve only own the vehicle for 2 yers and bought it at 65K. Currently at 77K.
Last edited by KenBad74; Jul 27, 2023 at 11:38 AM.
Out Of Control!!
Joined: Sep 2018
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From: unbegrenzt
2017 GLE350 4MATIC
Lean means there is unmetered air. This means a leak in the induction system.
Replace all PCV and purge/EVAP parts. These systems are garbage when brand new.
Look carefully at the intake manifold for possible manifold crack or leaky gasket.
The car will never run right if there is unmetered air.
Replace all PCV and purge/EVAP parts. These systems are garbage when brand new.
Look carefully at the intake manifold for possible manifold crack or leaky gasket.
The car will never run right if there is unmetered air.
Last edited by chassis; Jul 27, 2023 at 12:49 PM.
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C300
Lean means there is unmetered air. This means a leak in the induction system.
Replace all PCV and purge/EVAP parts. These systems are garbage when brand new.
Look carefully at the intake manifold for possible manifold crack or leaky gasket.
The car will never run right if there is unmetered air.
Replace all PCV and purge/EVAP parts. These systems are garbage when brand new.
Look carefully at the intake manifold for possible manifold crack or leaky gasket.
The car will never run right if there is unmetered air.
Since engine repairs were performed, I removed and checked all spark plugs, checked injector coding, inspected upper engine for unmetered air leaks. Only noticeable difference was that cylinder #3 is black in color, which is indicative of unburnt fuel in the cylinder. Spark plugs of cylinders 1-2 and 4 look new as they were all replaced with engine repairs. Checked injector performance data and found cylinder #3 ASH count is extremely high as if the injector is stuck open or the spark plug was not firing. With Xentry connected and spark plug #3 removed, I borescope the cylinder to look for and fuel leaking in from a stuck open injector. No fuel leakage found. Now I went to look for any obvious cause that could cause faulty Lambda control. There is a possibility that due to the engines condition upon arrival and finding the camshaft pulse wheel moved, that the engine could not correctly time itself, which in turn could create a fuel dump issue and contaminated the O2 sensors. Before leaning this way, I decided to smoke test the entire engine for any possible air leaks that could corrupt the mixture information. Smoke test revealed excessive smoke coming from under the charge air intercooler. Lifted car and removed belly pans. Found smoke omitting from behind the engine mount bracket that attached to the left side of the engine. \The only component behind the mount bracket is the crankcase vent line oil separator mounted to the block. These components have a high failure rate from the factory as new, and it is obvious that this has been replaced in the past. I also noticed with a mirror that the oil separator has oil on it as if it was leaking oil as well.
Replaced but issue remains.
Out Of Control!!
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From: unbegrenzt
2017 GLE350 4MATIC
From Mechanic
Since engine repairs were performed, I removed and checked all spark plugs, checked injector coding, inspected upper engine for unmetered air leaks. Only noticeable difference was that cylinder #3 is black in color, which is indicative of unburnt fuel in the cylinder. Spark plugs of cylinders 1-2 and 4 look new as they were all replaced with engine repairs. Checked injector performance data and found cylinder #3 ASH count is extremely high as if the injector is stuck open or the spark plug was not firing. With Xentry connected and spark plug #3 removed, I borescope the cylinder to look for and fuel leaking in from a stuck open injector. No fuel leakage found. Now I went to look for any obvious cause that could cause faulty Lambda control. There is a possibility that due to the engines condition upon arrival and finding the camshaft pulse wheel moved, that the engine could not correctly time itself, which in turn could create a fuel dump issue and contaminated the O2 sensors. Before leaning this way, I decided to smoke test the entire engine for any possible air leaks that could corrupt the mixture information. Smoke test revealed excessive smoke coming from under the charge air intercooler. Lifted car and removed belly pans. Found smoke omitting from behind the engine mount bracket that attached to the left side of the engine. \The only component behind the mount bracket is the crankcase vent line oil separator mounted to the block. These components have a high failure rate from the factory as new, and it is obvious that this has been replaced in the past. I also noticed with a mirror that the oil separator has oil on it as if it was leaking oil as well.
Replaced but issue remains.
Since engine repairs were performed, I removed and checked all spark plugs, checked injector coding, inspected upper engine for unmetered air leaks. Only noticeable difference was that cylinder #3 is black in color, which is indicative of unburnt fuel in the cylinder. Spark plugs of cylinders 1-2 and 4 look new as they were all replaced with engine repairs. Checked injector performance data and found cylinder #3 ASH count is extremely high as if the injector is stuck open or the spark plug was not firing. With Xentry connected and spark plug #3 removed, I borescope the cylinder to look for and fuel leaking in from a stuck open injector. No fuel leakage found. Now I went to look for any obvious cause that could cause faulty Lambda control. There is a possibility that due to the engines condition upon arrival and finding the camshaft pulse wheel moved, that the engine could not correctly time itself, which in turn could create a fuel dump issue and contaminated the O2 sensors. Before leaning this way, I decided to smoke test the entire engine for any possible air leaks that could corrupt the mixture information. Smoke test revealed excessive smoke coming from under the charge air intercooler. Lifted car and removed belly pans. Found smoke omitting from behind the engine mount bracket that attached to the left side of the engine. \The only component behind the mount bracket is the crankcase vent line oil separator mounted to the block. These components have a high failure rate from the factory as new, and it is obvious that this has been replaced in the past. I also noticed with a mirror that the oil separator has oil on it as if it was leaking oil as well.
Replaced but issue remains.
Time for a new mechanic. He is guessing and doesn’t know what the problem is, and spending your money along the way.
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C300
Not only that but he said this
Removed and replaced crankcase vent line assembly as recommended. During replacement, found 2 engine mount bracket bolts to the block loose and top 2 bolts of the oil separator at the block loose as well. The top 2 bolts keep the oil seperator sealed to the block. All indications point to this being the source of the air leak and the smoke seen during diagnosis.
Preview
So this means my original Crankcase vent assembly probably didn't need to be changed but instead of telling me his findings and giving me the option, he changed it out. Maybe for best just not for my wallet.
Removed and replaced crankcase vent line assembly as recommended. During replacement, found 2 engine mount bracket bolts to the block loose and top 2 bolts of the oil separator at the block loose as well. The top 2 bolts keep the oil seperator sealed to the block. All indications point to this being the source of the air leak and the smoke seen during diagnosis.
Preview
So this means my original Crankcase vent assembly probably didn't need to be changed but instead of telling me his findings and giving me the option, he changed it out. Maybe for best just not for my wallet.
Last edited by KenBad74; Jul 27, 2023 at 02:03 PM.
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C300
Error code progression
Just would like the correlation explained:
(p0016 only) code led to an intake canmshaft replacement with gears
car returned and driven 1 hour home and shut off
(p2188 Only) code diagnosed after towed back to repair shop. remedy: replace Crankcase ventalation valve
car returned with (P0303 only) code
How can codes pop up individually during each repair and be my responsibilty. Am I stuck on stupid?
(p0016 only) code led to an intake canmshaft replacement with gears
car returned and driven 1 hour home and shut off
(p2188 Only) code diagnosed after towed back to repair shop. remedy: replace Crankcase ventalation valve
car returned with (P0303 only) code
How can codes pop up individually during each repair and be my responsibilty. Am I stuck on stupid?
Joined: Nov 2016
Posts: 7,847
Likes: 3,496
From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Out Of Control!!
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
FYI... loose CPS causes bad timing
In case you run out of obvious causes... we just got done figuring the VVT reluctor wheel for CPS counting is built so it can loosely shift position and cause incorrect timings ie. misfirings.
VVT rattles are recognized to help worsen loose timing correlation.
VVT rattles are recognized to help worsen loose timing correlation.
Joined: Nov 2016
Posts: 7,847
Likes: 3,496
From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
