CEL On & Off, Rough Idle
Thread Starter
Super Member
Joined: Nov 2005
Posts: 673
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From: SoCal
F10
CEL On & Off, Rough Idle
The car is a 2005 c230 Sedan (4 cyl) with k&n filter installed at 12,000 miles, car has 19,000 miles now. here goes:
Last week I filled up the car, drove 38 milers to work and as I parked the car, it started to idle roughly and Check engine light (CEL) came on. I shut off the car, started it and same thing. 4 Hours later, I started the car, Idle is fine but CEL still ON. Called the dealer, they said check the gas cap, removed and retightened gas cap, Car is fine, no CEL.
6 Days later, same thing, I haven't filled up since the last time it happened, so I don't think it's the gas cap issue. Yesterday, it started to idle roughly again but the CEL did not come on. The car is fine for now, does anyone have any idea what's the issue here. I'm thinking of replacing the fuel filter as it may just be clogged. Any suggestions?
Last week I filled up the car, drove 38 milers to work and as I parked the car, it started to idle roughly and Check engine light (CEL) came on. I shut off the car, started it and same thing. 4 Hours later, I started the car, Idle is fine but CEL still ON. Called the dealer, they said check the gas cap, removed and retightened gas cap, Car is fine, no CEL.
6 Days later, same thing, I haven't filled up since the last time it happened, so I don't think it's the gas cap issue. Yesterday, it started to idle roughly again but the CEL did not come on. The car is fine for now, does anyone have any idea what's the issue here. I'm thinking of replacing the fuel filter as it may just be clogged. Any suggestions?
Thread Starter
Super Member
Joined: Nov 2005
Posts: 673
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From: SoCal
F10
i will bring it on for warranty work, thank you sir.
i'm just trippin b/c of the horrible stories i heard about these cars, and I really like the car, but if this little annoying things come up, I'm gonna have to let her go. I just hope it's a one time fix. thanks again
i'm just trippin b/c of the horrible stories i heard about these cars, and I really like the car, but if this little annoying things come up, I'm gonna have to let her go. I just hope it's a one time fix. thanks again
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Joined: Nov 2001
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From: Huntington Beach, Ca.
'17 Jaguar XF
Maybe your air filter contaminated the MAF? Just because the air filter is relatively new doesn't mean it was oiled correctly. I believe the wet/oiled air filters are a major source of MAF failures.....do some searching and you'll see.
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From: North Carolina
98 Black C43 , 12’ ML 350 Blutec
Originally Posted by mleskovar
Maybe your air filter contaminated the MAF? Just because the air filter is relatively new doesn't mean it was oiled correctly. I believe the wet/oiled air filters are a major source of MAF failures.....do some searching and you'll see.
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Joined: Nov 2001
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From: Huntington Beach, Ca.
'17 Jaguar XF
Originally Posted by C43AMG
I would highly doubt a K&N with 7,000 miles on it would have caused a MAF malfunction -.
Here's my theory after reading about MAF failures and the function of the unit: 'Wet' air filters rely on oil droplets to fine clean air as it passes over them. These droplets are continually under induction pressure to pull them from the foam and eventually enough minute droplets collect to form a big enough drop that finds it's way to the sensor. That's why some people have had good results cleaning the MAF. Some have reported seeing contamination/discoloration on the MAF wires prior to cleaning. More importantly....think of it this way....isn't the air cleaner supposed to stop contaminates from entering the combustion chamber?? How else could a MAF get contaminated unless the air filter wasn't doing it's job or even caused it?
MBWorld Fanatic!
Joined: Feb 2005
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From: North Carolina
98 Black C43 , 12’ ML 350 Blutec
Originally Posted by mleskovar
How else could a MAF get contaminated unless the air filter wasn't doing it's job or even caused it?
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MBWorld Fanatic!
Joined: Nov 2001
Posts: 5,851
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From: Huntington Beach, Ca.
'17 Jaguar XF
Originally Posted by C43AMG
How about the airbox not being seated properly- after filter replacement - allowing contaminates to bypass the filter and enter the engine directly.
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Joined: Mar 2006
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From: Dublin, OH
05 ML350, 85 300D
It is a Technical Bulletin... fixes that come out after the car has been on the road- every manufacturer has them. Recalls are generally safety related, or something that WILL fail for sure. DTBs are issues that not every car will have- like your cylinder head, it's due to carbon buildup on the exhaust valves, so the car misfires under certain conditions- it won't happen to everyone, based on how you drive the car, type of fuel you use,etc..
