I'm a first time benz owner, and i just fell in love with the car when i seen it. One little problem, the car shakes when it idles when i first turn it on not after driving. Wondering location of MAF sensor, and The Hose from the supercharger that ive read plagued these cars. Any input would be greatly appreciated.
Not sure about the 1.8lt m271, but the 2.3lt m111 in the 02' coupe idles rough on cold start for about 15-30 seconds. This is normal for the engine. If it seems really rough for an extended period of time you might need to clean the MAFS, or possibly change the plugs. How many miles does the vehicle have?
__________________ My Car;02' C230 Kompressor Sportcoupe[115,000 Miles] Modifications: ASP Overdrive Pulley - NGK Iridium IX Sparkplugs - Kompressor Silencer Removed ---------------- Clear Side Indicator Covers
104,000 i bought it used with 103 and i haven not had the car very long, the strange thing is it seemed to start when the weather got a little warmer i bought the car on a below zero day, and the frigged temps did not seem to bother at first but every once and a while rough idle. Thanks a ton for responding you guys have some pretty decent info and i hope to find more things out cuz the car is a blast to drive. Once again thanx for reply.
As far as the rough idle I just had the repair done on my '05. It is a recall so you may qualify to get it done for free from dealer. The rough idle generally occured just at start up for me and then would go away once the car warmed up. The hose should be located under the air filter box and it should go from engine to supercharger. Not 100% sure but fairly sure. As far as the recall it is campaign number 2008020002. You should call the dealer and see if your car is part of the recall. It would be nice to be able to get it done for free.
The MAF sensor should be located in the air intake somewhere after the air filter. Again not 100% sure.
if the engine was O.K. at below zero and doing that in warm I would bet on one of coil. When the temp is below zero the air is dry and when is above you have some humidity in the air which cause the misfire(after engine is hot it is O.K becouse everything is dry) check for sparks in the dark garage in the humid morning ,you may see some.
Do you know if the recall is affecting the '03's. I bought the car used so if it did have a recall would the dealer have to fix it? Also i just popped the hood on the thing this weeked because it was finally nice and took a look at what i assumed were the coils, and opened up my air filter. Everything is a STAR or torx type bit or socket what so you use. Its all very new to me so the input is grately apericated.
So for 2003 there are a few catastrophic problem that can cause a rough idle and then of course gets worse from there (you may not want to hear this so click close on your browser before continuing) -
1. there's a service campaign (not a recall) on the pcv hose, take it to dealer, they will know what to do. Typically this triggers a CEL for a lean fuel trim error. Doesn't matter, dealer will replace anyway for free regardless of if this is a problem with your car or not.
2. 2003 up to early 2004 had a defect in the design of the head. It will build up carbon and prevent the valve from seating and walla, rough idle that gets progressively worse. Because of the way it happens, you will not likely get a CEL. Fix is to replace head, figure a few thousand to fix (part is $2K). You can remove head and clean valves but you'll just have it happen again. New head is a different design.
3. 2003-2005 has a problem with the cam sensors leaking into the wiring harness. There is a TSB for 2003 only that puts a harness extension on by the cam sensor to prevent oil from leaking into the harness. If it has already leaked you will get an O2 sensor error, it will costs thousands to fix as you'll have to replace O2 sensor and engine wiring harness and of course the 2 cam sensors.
4. 2003 and early 2004 may have a radiator from Valeo, not good. They leak internally into the transmission. You can tell you have Valeo from a sticker at the bottom of the radiator. Not a problem if you have a manul trans. If it has started leaking, you may need a new transmission and of course a new radiator.
So for 2003 there are a few catastrophic problem that can cause a rough idle and then of course gets worse from there (you may not want to hear this so click close on your browser before continuing) -
1. there's a service campaign (not a recall) on the pcv hose, take it to dealer, they will know what to do. Typically this triggers a CEL for a lean fuel trim error. Doesn't matter, dealer will replace anyway for free regardless of if this is a problem with your car or not.
2. 2003 up to early 2004 had a defect in the design of the head. It will build up carbon and prevent the valve from seating and walla, rough idle that gets progressively worse. Because of the way it happens, you will not likely get a CEL. Fix is to replace head, figure a few thousand to fix (part is $2K). You can remove head and clean valves but you'll just have it happen again. New head is a different design.
3. 2003-2005 has a problem with the cam sensors leaking into the wiring harness. There is a TSB for 2003 only that puts a harness extension on by the cam sensor to prevent oil from leaking into the harness. If it has already leaked you will get an O2 sensor error, it will costs thousands to fix as you'll have to replace O2 sensor and engine wiring harness and of course the 2 cam sensors.
4. 2003 and early 2004 may have a radiator from Valeo, not good. They leak internally into the transmission. You can tell you have Valeo from a sticker at the bottom of the radiator. Not a problem if you have a manul trans. If it has started leaking, you may need a new transmission and of course a new radiator.
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Seems w203's have serious problems than my w202! I am however considering buying w203 and with the above problems I think I will avoid the 2003-2005 range ( how sad) If I have to consider 2001-2002 are there any serious issues like those above that I need to be aware of before I jump on the deep end?
I have so far enjoyed my benz ride and would like to change (upgrade), your input will be greatly appreaciated. Thanks
You can get 2003-2005, avoid 4 cyl. but the reality is that its a Benz, they are built to be disposable after the 4yr/50k exp date. Just get a new one, the additional cost on the payment will be less than the repairs on a 6-7 year old Benz, probably cheaper than an extended warranty if you can get one on a car that old.
Rough idle 2003 C230 kopmpressor coupe 
Linear Mode
