ML63 Misfire
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Mercedes ML63 164 2009
ML63 Misfire
I've got a bad misfire in cylinder 8 and I think I have narrowed it down to the coil pack. Going to swap that coil into another cylinder and see if the problem follows. Has anyone else experienced a random misfire that just appeared out of the blue? it goes away after I clear the CEL but comes back within 5mins. When I hooked up my scan tool I noticed that one of the MAF's is showing a flow rate while the car is off (Maybe explaining why the car runs so rich all the time 
) If anyone has had this happen id love to know how things turned out for you!
EDIT: Wrong Section Sorry!
) If anyone has had this happen id love to know how things turned out for you!EDIT: Wrong Section Sorry!
Last edited by ITech; Jul 20, 2020 at 07:56 PM.
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From: Snowville, ID
W212 E350; W166 GLC300; W164 ML550; W164 ML63; W221 S65; W220 S430; Escalade ESV
I just had misfired on #4 couples day ago. Background, misfired came and go on my ML63 a few times and I didn't bother to look up the codes. Spark plugs were replaced 20000 miles ago.
Couple days ago, CEL came and stay and the car has no power. P0304 came up so I swapped #1 coil with #4 coil. Before placing #1 coil on cylinder #4, I placed some dielectric grease on both coil springs. No more engine shaking and no more CEL after the swaps so I guess the problem was just contact issue.
Couple days ago, CEL came and stay and the car has no power. P0304 came up so I swapped #1 coil with #4 coil. Before placing #1 coil on cylinder #4, I placed some dielectric grease on both coil springs. No more engine shaking and no more CEL after the swaps so I guess the problem was just contact issue.
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Mercedes ML63 164 2009
I just had misfired on #4 couples day ago. Background, misfired came and go on my ML63 a few times and I didn't bother to look up the codes. Spark plugs were replaced 20000 miles ago.
Couple days ago, CEL came and stay and the car has no power. P0304 came up so I swapped #1 coil with #4 coil. Before placing #1 coil on cylinder #4, I placed some dielectric grease on both coil springs. No more engine shaking and no more CEL after the swaps so I guess the problem was just contact issue.
Couple days ago, CEL came and stay and the car has no power. P0304 came up so I swapped #1 coil with #4 coil. Before placing #1 coil on cylinder #4, I placed some dielectric grease on both coil springs. No more engine shaking and no more CEL after the swaps so I guess the problem was just contact issue.
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From: Cleveland OHIO
01 ML55AMG 04 ML500 03 ML350 08 ML63AMG
Yeah id start from coil pack. I had that happen on my W163 a lot. Switch and see what happens. and wile you doing that clean your mass airflow sensor. and if you have a lot of miles id do spark plugs.Good luck!
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Mercedes ML63 164 2009
Swapped coils and still Cylinder #8 misfire 
I did get a fuel injector error for cylinder 8. I'm going to run fresh cables from the injector to the ECU tomorrow because this car has had issues with this side of the harness as it stupidly goes under the intake manifold and gets munted. Also got a code for the bank 2 knock sensor which also leads me to believe the wiring is bad. I hope this fixes the issue otherwise I'm taking it to a local indie shop that will charge 100's for diagnosis and fix.
I did get a fuel injector error for cylinder 8. I'm going to run fresh cables from the injector to the ECU tomorrow because this car has had issues with this side of the harness as it stupidly goes under the intake manifold and gets munted. Also got a code for the bank 2 knock sensor which also leads me to believe the wiring is bad. I hope this fixes the issue otherwise I'm taking it to a local indie shop that will charge 100's for diagnosis and fix.
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From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
What #7 says is that there are 3 possibilities for misfires:
Misfires caused by ignition system faults
Misfiring through fuel starvation
Misfiring because of miscellaneous causes
Misfires caused by ignition system faults
Misfiring through fuel starvation
Misfiring because of miscellaneous causes
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Mercedes ML63 164 2009
Taken the car down to the local indyshop and they believe that the manifold is cracked. I’ve not had a chance to take a look myself yet but I don’t believe that it’s the issue. My manifold does have a small crack where the fuel rail connects above cylinder #5 which would not cause cylinder #8 to misfire? The issue also seems to be intermittent as ive managed to drive for 20mins no issues and other times it misfires right from the get go. Personally I believe the issue lies in the O2 sensors as I have a circuit error code for the second bank but my mechanic claims to not understand the output from my OBD scanner 
The Indy doesn’t want to take off the manifold without me there as he claims it will crack completely. I’m going to get them to check those darn O2 sensors tomorrow before I head down.
I’ll keep this thread updated as I get some more info.
The Indy doesn’t want to take off the manifold without me there as he claims it will crack completely. I’m going to get them to check those darn O2 sensors tomorrow before I head down.
I’ll keep this thread updated as I get some more info.
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Mercedes ML63 164 2009
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Mercedes ML63 164 2009
