c300 rough start when cold
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2011 c300 4matic
c300 rough start when cold
is that normal that it starts kinda rough when cold but starts normal when warm?
its not a rod knock(i have experience with that) its just rough like when you wake up at the wrong time in the morning and you cant figure out how to operate your own legs to go to bathroom kind of rough.
alot of shaking.
but again no codes
its not a rod knock(i have experience with that) its just rough like when you wake up at the wrong time in the morning and you cant figure out how to operate your own legs to go to bathroom kind of rough.
alot of shaking.
but again no codes
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Joined: May 2009
Posts: 209
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2011 c300 4matic
shop scanner.
there is no engine specific codes
i replaced manifold already and did a basic tuna
do i have to program the new manifold in any way after i replace it?(the flaps were broken on the old one)
it fumbles rather hard for about 3-5 seconds on initial vold start but is fine when warmed up start
only codes are electrical for rear fuse box and some kind of 30g circuit which i still cant find what it is
there is no engine specific codes
i replaced manifold already and did a basic tuna
do i have to program the new manifold in any way after i replace it?(the flaps were broken on the old one)
it fumbles rather hard for about 3-5 seconds on initial vold start but is fine when warmed up start
only codes are electrical for rear fuse box and some kind of 30g circuit which i still cant find what it is
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)
shop scanner.
there is no engine specific codes
i replaced manifold already and did a basic tuna
do i have to program the new manifold in any way after i replace it?(the flaps were broken on the old one)
it fumbles rather hard for about 3-5 seconds on initial vold start but is fine when warmed up start
only codes are electrical for rear fuse box and some kind of 30g circuit which i still cant find what it is
there is no engine specific codes
i replaced manifold already and did a basic tuna
do i have to program the new manifold in any way after i replace it?(the flaps were broken on the old one)
it fumbles rather hard for about 3-5 seconds on initial vold start but is fine when warmed up start
only codes are electrical for rear fuse box and some kind of 30g circuit which i still cant find what it is
You many need to do some sort of "teach in" for the new manifold.
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From: Walnut Creek, CA
325Ci, 325Cic, C300
is that normal that it starts kinda rough when cold but starts normal when warm?
its not a rod knock(i have experience with that) its just rough like when you wake up at the wrong time in the morning and you cant figure out how to operate your own legs to go to bathroom kind of rough.
alot of shaking.
but again no codes
its not a rod knock(i have experience with that) its just rough like when you wake up at the wrong time in the morning and you cant figure out how to operate your own legs to go to bathroom kind of rough.
alot of shaking.
but again no codes
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From: MA Coast
W204 2010 C300 4matic Sport M272
What engine, M272?
Im guessing, initial rough running then it evens out may be a vacuum line issue somewhere. Especially if you recently replaced the intake manifold.
Im guessing, initial rough running then it evens out may be a vacuum line issue somewhere. Especially if you recently replaced the intake manifold.
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From: Walnut Creek, CA
325Ci, 325Cic, C300
194k with no history of mounts being changed, the mount arm is probably already in direct contact with mount body, because internal isolation material has collapsed. You can check this from the engine bay with a proper inspection mirror and a good flashlight.
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2011 c300 4matic
Its more of an engine fumble rather than car shaking
i know the mounts are shot and i can feel it when driving/shifting etc.
this is more of an engine having a kind of rude awakening like your first night in bootcamp and then it evens out and runs smoother.
its also same rpm that im having the rpm fluctuation when i drive.
it was there before i replaced the manifold
vacuum leak would be present all the time also.
i know the mounts are shot and i can feel it when driving/shifting etc.
this is more of an engine having a kind of rude awakening like your first night in bootcamp and then it evens out and runs smoother.
its also same rpm that im having the rpm fluctuation when i drive.
it was there before i replaced the manifold
vacuum leak would be present all the time also.
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2011 c300 4matic
there seems to be 2 different sets of mounts and they both say awd
which one is actual awd lol
one set with aluminum tranny mount and the above motor mounts
the other one with pancake tranny mount and what looks like a glazed donut for engine mounts
which one is actual awd lol
one set with aluminum tranny mount and the above motor mounts
the other one with pancake tranny mount and what looks like a glazed donut for engine mounts
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2011 c300 4matic
Part two.
weather got colder
34degrees now
after sitting for 2 days i started the car and idle went down to 750rpm in less than a minute and idles like its a misfire
the only code is for the intermittent left catalytic converter insufficient something that has been on and off for last 6 months.
would be so much easier if it threw a code for something actually related to problem
weather got colder
34degrees now
after sitting for 2 days i started the car and idle went down to 750rpm in less than a minute and idles like its a misfire
the only code is for the intermittent left catalytic converter insufficient something that has been on and off for last 6 months.
would be so much easier if it threw a code for something actually related to problem
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2011 c300 4matic
Ok so 10 minutes later i started it after 5 min drive to the store snd it runs like it was before.
wtf lol
anyone want to buy my mercedes? I feel like im not into that kind of life anymore
wtf lol
anyone want to buy my mercedes? I feel like im not into that kind of life anymore
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2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
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2011 c300 4matic
well a porsche either runs or its a long "project" in the garage.
mercedes does that bullsht where it runs then it doesnt you cycle the key and it runs normal again.
we had about 10 mercedeseses in the family in last 20 years and they all have these issues
but anyway i ordered launch scanner hopefully it picks up something that my old autel missed.
mercedes does that bullsht where it runs then it doesnt you cycle the key and it runs normal again.
we had about 10 mercedeseses in the family in last 20 years and they all have these issues
but anyway i ordered launch scanner hopefully it picks up something that my old autel missed.
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Joined: Apr 2019
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
CAN Bandwidth vs. ECU performance
well a porsche either runs or its a long "project" in the garage.
mercedes does that bullsht where it runs then it doesnt you cycle the key and it runs normal again.
we had about 10 mercedeseses in the family in last 20 years and they all have these issues
but anyway i ordered launch scanner hopefully it picks up something that my old autel missed.
mercedes does that bullsht where it runs then it doesnt you cycle the key and it runs normal again.
we had about 10 mercedeseses in the family in last 20 years and they all have these issues
but anyway i ordered launch scanner hopefully it picks up something that my old autel missed.
Your best interest is to have a pristine networks else timings will be impacted the way you've described.
The fault tolerance impacts the performance.
Lets see your Launch report...
Your rough cold engine may be lean fuel trim linked to lower performance.
Last edited by CaliBenzDriver; Dec 7, 2024 at 06:33 PM.
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2011 c300 4matic
if i disconnect battery and remove sam modules (both front and rear) for inspection do i have to do any kind of re learning process or wil they plug in and work again like nothing happened?
Out Of Control!!
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
I second that!
Part of the chassis is always awake.
Disconnect all power prior to unplugging any module... powered on while in "sleep mode" Even in "low power mode" power is still applied.
Part of the chassis is always awake.
Disconnect all power prior to unplugging any module... powered on while in "sleep mode" Even in "low power mode" power is still applied.
Last edited by CaliBenzDriver; Dec 11, 2024 at 08:25 PM.
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2011 c300 4matic
does mercedes dealership software have sam module troubleshooting?
i have vxdiag jbox dont have mb licence for it yet but was wondering if its worth having and would give me access to more precision troubleshooting options
i have vxdiag jbox dont have mb licence for it yet but was wondering if its worth having and would give me access to more precision troubleshooting options
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From: Northern Indiana
2014 c300 w204.080 3.5 v6
@BenzNinja has the best software best hardware and software for troubleshooting. It's a little pricy butt you will also get personal support along with the package.
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Rough idle fluctuation
Its more of an engine fumble rather than car shaking
i know the mounts are shot and i can feel it when driving/shifting etc.
this is more of an engine having a kind of rude awakening like your first night in bootcamp and then it evens out and runs smoother.
its also same rpm that im having the rpm fluctuation when i drive.
it was there before i replaced the manifold
vacuum leak would be present all the time also.
i know the mounts are shot and i can feel it when driving/shifting etc.
this is more of an engine having a kind of rude awakening like your first night in bootcamp and then it evens out and runs smoother.
its also same rpm that im having the rpm fluctuation when i drive.
it was there before i replaced the manifold
vacuum leak would be present all the time also.
