Strange Idle After Plug Change
#1
Member
Thread Starter
Strange Idle After Plug Change
Hey guys.
recently changed spark plugs. Like 4 days ago. Car developed a light eratic idle in park or at a stop in drive.
Ran some diagnostics and saw cylinder 4 has a lot of erratic movement. Changed the 2 plugs.
it has smoothed out but ran diagnostics again today and can see it’s still running a tad erratic.
what else can I check. I’m being told it’s now either coil pack. O2 sensor or even injectors.
any advise :-(.
car has 300 000 kms. Never missed service. All other cylinders showing tiny adjustments of -0.63 then 0. Cylinder 4 went as high a 3.16.
was worse before replacement of the 2 plugs.
recently changed spark plugs. Like 4 days ago. Car developed a light eratic idle in park or at a stop in drive.
Ran some diagnostics and saw cylinder 4 has a lot of erratic movement. Changed the 2 plugs.
it has smoothed out but ran diagnostics again today and can see it’s still running a tad erratic.
what else can I check. I’m being told it’s now either coil pack. O2 sensor or even injectors.
![](https://cimg4.ibsrv.net/gimg/www.mbworld.org-vbulletin/2000x1504/img_1271_86b2cda04647dfb39cb74aa1f22c2784e71db40c.jpeg)
![](https://cimg5.ibsrv.net/gimg/www.mbworld.org-vbulletin/2000x1504/img_1270_e1d90ea2877cfdf7f7e341fa3bef65e06a43ddc8.jpeg)
any advise :-(.
car has 300 000 kms. Never missed service. All other cylinders showing tiny adjustments of -0.63 then 0. Cylinder 4 went as high a 3.16.
was worse before replacement of the 2 plugs.
#4
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2005 CLK320 Cabriolet
Did you change the wires as well?
Here is a link to my story about a more serious problem with idling stability. Might offer you some insights and ideas for coaxng out the problems.
https://www.benzworld.org/threads/05...#post-18631310
Here is a link to my story about a more serious problem with idling stability. Might offer you some insights and ideas for coaxng out the problems.
https://www.benzworld.org/threads/05...#post-18631310
#5
MBWorld Fanatic!
No chance it could be defective spark plugs?
#6
Junior Member
Hey guys.
recently changed spark plugs. Like 4 days ago. Car developed a light eratic idle in park or at a stop in drive.
Ran some diagnostics and saw cylinder 4 has a lot of erratic movement. Changed the 2 plugs.
it has smoothed out but ran diagnostics again today and can see it’s still running a tad erratic.
what else can I check. I’m being told it’s now either coil pack. O2 sensor or even injectors.
any advise :-(.
car has 300 000 kms. Never missed service. All other cylinders showing tiny adjustments of -0.63 then 0. Cylinder 4 went as high a 3.16.
was worse before replacement of the 2 plugs.
recently changed spark plugs. Like 4 days ago. Car developed a light eratic idle in park or at a stop in drive.
Ran some diagnostics and saw cylinder 4 has a lot of erratic movement. Changed the 2 plugs.
it has smoothed out but ran diagnostics again today and can see it’s still running a tad erratic.
what else can I check. I’m being told it’s now either coil pack. O2 sensor or even injectors.
![](https://cimg4.ibsrv.net/gimg/www.mbworld.org-vbulletin/2000x1504/img_1271_86b2cda04647dfb39cb74aa1f22c2784e71db40c.jpeg)
![](https://cimg5.ibsrv.net/gimg/www.mbworld.org-vbulletin/2000x1504/img_1270_e1d90ea2877cfdf7f7e341fa3bef65e06a43ddc8.jpeg)
any advise :-(.
car has 300 000 kms. Never missed service. All other cylinders showing tiny adjustments of -0.63 then 0. Cylinder 4 went as high a 3.16.
was worse before replacement of the 2 plugs.