Jun 15, 2015, 04:23 PM
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Check engine light and really rough idle
Thread Starter
Super Moderator Alumni
Joined: Oct 2002
Posts: 8,692
Likes: 58
From: So Cal.
2019 GT3 RS, 2017 M3 30 Jahre
Check engine light and really rough idle
Today I decided to go to Las Vegas. My C230WZ drove really well up until we got to Barstow. When I was parking, it started to shake really bad. So I got my coffee and then went back to my car and checked the oil through the MFD--it was ok. Then when I started the car it was idling rough and the check engine light came on. After multiple restarts, talking to roadside, and even opening the gas cap for 5 mins. Nothing changed. Roadside said they can tow it (100 miles min each way) but it was safe to drive. So I continued my trip. It drove really smoothly and had no issues aside from the idle and light. I'm in Vegas now posting on my Treo. Should I be concerned about my car? I've had the light in the past w/my old MBs but not this rough idle. Anyone have the same prob? Advice? Thanks!
Member
Joined: Jun 2005
Posts: 198
Likes: 0
From: SoCal
2005 C230 K and 2009 Smart
i also had the same problem with my car about 6 or 7 mos ago the problem was the car was misfiring in cylinder 3 so they looked at it and found that there was moisture in all the spark plugs and changed all for of them now no sign of that problem i dont know if your situation is the same but sounds like mine
MBWorld Fanatic!
Joined: Jan 2005
Posts: 2,848
Likes: 15
From: Orange County
2005 C Wagon (No snickering please!)
Originally Posted by FrankW
still deciding if I should drive my car up to vegas or try to borrow my dad's new Odyssey. i'm going with friends from high school.
I am not sure about the four cylinder car, but many other engine management systems have a valve called ISC (idle speed control) that allows air to bypass the throttle plate when going to idle. A little sticky stuff on that valve or the dirt in the passages can cause the car to run rough or even die at idle, but run fine at higher RPM. If the ECU (Mercedes calls it the ME-SFI) can't position the valve to it's liking, it can turn on the check engine light.
Super Member
Joined: Sep 2004
Posts: 630
Likes: 1
From: nJ/pHiLLy/nY
Audi 225 TT.w203 sedan.Bmw 318tiCali.Ed.VW Jetta vr6
im having the same exact problems, my check engine light came on about a week ago and when i come to a stop i have a bad rough idle untill i hit the gas, 
going in for service tommorow..... 
going in for service tommorow.....
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Joined: Jul 2005
Posts: 72
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From: lbc
2005 c230k
i had the same problem. took her in and the initial diagnostic was it was misfiring and hitting on only 3 cyclinders. after further investigation, they replaced my purge valve. she's running even better than before, but does seems to idle a tiny bit rough.
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Thread Starter
Super Moderator Alumni
Joined: Oct 2002
Posts: 8,692
Likes: 58
From: So Cal.
2019 GT3 RS, 2017 M3 30 Jahre
WTF?!?! this is bull****, it seems like all of us have 05's and they all have these issues. this should not happen at all...
I just took it in an hour ago, we'll see what they say.
I had my w202 for 7 years, and not once in those years did this bull**** happen.
I really liked my car up until this point and I was excited to get a new one, but this may indeed be my last MB.
I just took it in an hour ago, we'll see what they say.
I had my w202 for 7 years, and not once in those years did this bull**** happen.
I really liked my car up until this point and I was excited to get a new one, but this may indeed be my last MB.
Thread Starter
Super Moderator Alumni
Joined: Oct 2002
Posts: 8,692
Likes: 58
From: So Cal.
2019 GT3 RS, 2017 M3 30 Jahre
ok, now I've heard it ALL.
the dealer called and said it was all done. there were no mechanical problems whatsoever, they checked everything... pressure test, oil, they listed off a bunch of stuff. they said they "flashed" it and installed a new "patch". now they say it's running fine. WTF?!?! this was caused by a firmware issue? so ****ing lame!
the dealer called and said it was all done. there were no mechanical problems whatsoever, they checked everything... pressure test, oil, they listed off a bunch of stuff. they said they "flashed" it and installed a new "patch". now they say it's running fine. WTF?!?! this was caused by a firmware issue? so ****ing lame!
Member
Joined: Mar 2005
Posts: 172
Likes: 3
From: Portland, OR
2005 C230 Kompressor Sport Sedan
Same issue
At 6,600 miles, my car had a rough idle with check engine light. Service did the following:
R&R Spark Plugs and boroscoped cylinders, carbon build up on valve stems.
Tedious, very tedious.
R&R Spark Plugs and boroscoped cylinders, carbon build up on valve stems.
Tedious, very tedious.
Thread Starter
Super Moderator Alumni
Joined: Oct 2002
Posts: 8,692
Likes: 58
From: So Cal.
2019 GT3 RS, 2017 M3 30 Jahre
Originally Posted by SteveAustin
At 6,600 miles, my car had a rough idle with check engine light. Service did the following:
R&R Spark Plugs and boroscoped cylinders, carbon build up on valve stems.
Tedious, very tedious.
R&R Spark Plugs and boroscoped cylinders, carbon build up on valve stems.
Tedious, very tedious.
but, they replaced a few things, a hose (271-018-06-82) and a loom time (005-997-49-90)
MBWorld Fanatic!
Joined: Nov 2001
Posts: 6,211
Likes: 2
From: Laguna Niguel, CA
Dont' worry, MBs get better with age. They build them so that you get the opportunity to test it and work out all the kinks, after a year or so you'll see, it will be almost as realiable as any American car.
