M112 Misfires
Thread Starter
Newbie
Joined: May 2008
Posts: 1
Likes: 0
W202
M112 Misfires
Hi all,
Been a member here for some time but have never needed to post anything as have always found the answer I needed by searching but this one has me stumped....
I have a 1999 C240 W202 and its always run fine up until recently. Then it developed a small intermittent misfire which was cured by changing plugs and a coil pack. Ran another 6 months ok afterwards (though there was the odd misfire once or twice that just went away by itself).
Then last week the misfire cam back with a vengeance. The car is pretty much undrivable with virtually no power at all.
Went the usual route of replacing all the plugs. No difference. Bought a coilpack and moved it round the engine and got a small improvement. Bought another and repeated the process and got another small improvement (had identified two lazy cylinders in the initial coil pack shuffle). Today replaced all the leads and no difference at all.
Thing is the car will (usually) fire up with no misfire at all. You can rev it in neutral, idle it for half an hour no problems. If you try and drive it it goes for about a mile or so no probs. Then it drops a cylinder and becomes all sluggish again. You can also provoke the problem by putting your foot down hard as well.
So I'm now beat. Anyone have a clue as to what is causing this???
Have seen other threads suggesting MAF, fuel filter and crank position sensor. Of these the fuel filter is my next candidate unless anyone has a better idea....
Been a member here for some time but have never needed to post anything as have always found the answer I needed by searching but this one has me stumped....
I have a 1999 C240 W202 and its always run fine up until recently. Then it developed a small intermittent misfire which was cured by changing plugs and a coil pack. Ran another 6 months ok afterwards (though there was the odd misfire once or twice that just went away by itself).
Then last week the misfire cam back with a vengeance. The car is pretty much undrivable with virtually no power at all.
Went the usual route of replacing all the plugs. No difference. Bought a coilpack and moved it round the engine and got a small improvement. Bought another and repeated the process and got another small improvement (had identified two lazy cylinders in the initial coil pack shuffle). Today replaced all the leads and no difference at all.
Thing is the car will (usually) fire up with no misfire at all. You can rev it in neutral, idle it for half an hour no problems. If you try and drive it it goes for about a mile or so no probs. Then it drops a cylinder and becomes all sluggish again. You can also provoke the problem by putting your foot down hard as well.
So I'm now beat. Anyone have a clue as to what is causing this???
Have seen other threads suggesting MAF, fuel filter and crank position sensor. Of these the fuel filter is my next candidate unless anyone has a better idea....
Junior Member
Joined: May 2016
Posts: 31
Likes: 0
2000 CLK 320
Hi all,
Been a member here for some time but have never needed to post anything as have always found the answer I needed by searching but this one has me stumped....
I have a 1999 C240 W202 and its always run fine up until recently. Then it developed a small intermittent misfire which was cured by changing plugs and a coil pack. Ran another 6 months ok afterwards (though there was the odd misfire once or twice that just went away by itself).
Then last week the misfire cam back with a vengeance. The car is pretty much undrivable with virtually no power at all.
Went the usual route of replacing all the plugs. No difference. Bought a coilpack and moved it round the engine and got a small improvement. Bought another and repeated the process and got another small improvement (had identified two lazy cylinders in the initial coil pack shuffle). Today replaced all the leads and no difference at all.
Thing is the car will (usually) fire up with no misfire at all. You can rev it in neutral, idle it for half an hour no problems. If you try and drive it it goes for about a mile or so no probs. Then it drops a cylinder and becomes all sluggish again. You can also provoke the problem by putting your foot down hard as well.
So I'm now beat. Anyone have a clue as to what is causing this???
Have seen other threads suggesting MAF, fuel filter and crank position sensor. Of these the fuel filter is my next candidate unless anyone has a better idea....
Been a member here for some time but have never needed to post anything as have always found the answer I needed by searching but this one has me stumped....
I have a 1999 C240 W202 and its always run fine up until recently. Then it developed a small intermittent misfire which was cured by changing plugs and a coil pack. Ran another 6 months ok afterwards (though there was the odd misfire once or twice that just went away by itself).
Then last week the misfire cam back with a vengeance. The car is pretty much undrivable with virtually no power at all.
Went the usual route of replacing all the plugs. No difference. Bought a coilpack and moved it round the engine and got a small improvement. Bought another and repeated the process and got another small improvement (had identified two lazy cylinders in the initial coil pack shuffle). Today replaced all the leads and no difference at all.
Thing is the car will (usually) fire up with no misfire at all. You can rev it in neutral, idle it for half an hour no problems. If you try and drive it it goes for about a mile or so no probs. Then it drops a cylinder and becomes all sluggish again. You can also provoke the problem by putting your foot down hard as well.
So I'm now beat. Anyone have a clue as to what is causing this???
Have seen other threads suggesting MAF, fuel filter and crank position sensor. Of these the fuel filter is my next candidate unless anyone has a better idea....
Newbie
Joined: Nov 2017
Posts: 3
Likes: 0
1998
w202
Hi all,
Been a member here for some time but have never needed to post anything as have always found the answer I needed by searching but this one has me stumped....
I have a 1999 C240 W202 and its always run fine up until recently. Then it developed a small intermittent misfire which was cured by changing plugs and a coil pack. Ran another 6 months ok afterwards (though there was the odd misfire once or twice that just went away by itself).
Then last week the misfire cam back with a vengeance. The car is pretty much undrivable with virtually no power at all.
Went the usual route of replacing all the plugs. No difference. Bought a coilpack and moved it round the engine and got a small improvement. Bought another and repeated the process and got another small improvement (had identified two lazy cylinders in the initial coil pack shuffle). Today replaced all the leads and no difference at all.
Thing is the car will (usually) fire up with no misfire at all. You can rev it in neutral, idle it for half an hour no problems. If you try and drive it it goes for about a mile or so no probs. Then it drops a cylinder and becomes all sluggish again. You can also provoke the problem by putting your foot down hard as well.
So I'm now beat. Anyone have a clue as to what is causing this???
Have seen other threads suggesting MAF, fuel filter and crank position sensor. Of these the fuel filter is my next candidate unless anyone has a better idea....
Been a member here for some time but have never needed to post anything as have always found the answer I needed by searching but this one has me stumped....
I have a 1999 C240 W202 and its always run fine up until recently. Then it developed a small intermittent misfire which was cured by changing plugs and a coil pack. Ran another 6 months ok afterwards (though there was the odd misfire once or twice that just went away by itself).
Then last week the misfire cam back with a vengeance. The car is pretty much undrivable with virtually no power at all.
Went the usual route of replacing all the plugs. No difference. Bought a coilpack and moved it round the engine and got a small improvement. Bought another and repeated the process and got another small improvement (had identified two lazy cylinders in the initial coil pack shuffle). Today replaced all the leads and no difference at all.
Thing is the car will (usually) fire up with no misfire at all. You can rev it in neutral, idle it for half an hour no problems. If you try and drive it it goes for about a mile or so no probs. Then it drops a cylinder and becomes all sluggish again. You can also provoke the problem by putting your foot down hard as well.
So I'm now beat. Anyone have a clue as to what is causing this???
Have seen other threads suggesting MAF, fuel filter and crank position sensor. Of these the fuel filter is my next candidate unless anyone has a better idea....
