Idle Problem & Check engine light 2003 C230
1) P2061
2) P201b
3) P2044
4) P201a
The actual problem with the rough idle seems to occur when stopped and the car attempts to idle. Check engine lights seems to come on and off
somewhat randomly.
Any help is greatly appreciated.
Thanks,
Steve
Email: sdcgkc@gmail.com
https://mbworld.org/forums/c-class-w203/199047-help-rough-idle-check-engine-light-codes-p0301-p0302-p0303-p0304.html
Rough idle but running OK at speed sometimes is indicitive of a vacuum leak, and this hose seems to be a somewhat common problem, especially on the '03s.
You should try searching in this forum on those codes and rough idle, and then do some reading. There's a sticky at the top of the forum with help on searching. Good luck!
I took it to a mechanic, he says I need a new MAF sensor.
BUT, after doing some research and receiving input from others, I realized that the problem is most likely what's known as "the $12 hose".
It's a hose connected to the supercharger. It's made of rubber, and if it cracks/breaks, it can cause the problems that are happening to your car and mine.
Better to get that checked first than spend hundreds on a new MAF sensor plus labor.
I've heard of people replacing their MAF sensor, etc, and the problem all along was that $12 hose...
how many miles are on your car? I have about 49,300. My problem started after we had temperatures below zero last week.
I wonder if there's a hose made of a more durable material that can be used instead of the rubber one.
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After doing research I realized that a lot of people fixed their problem with that hose. Funny how this problem is affecting 2003 c230 owners around the same time.
I'm not sure if there are 1 or 2 different $12 hoses...Maybe just one.
Any unusual noise coming from your engine when it's parked?
The hose has apparently gone thru 3 part # iterations, so one would hope they have revised it to last longer. If mine ever goes again, I will look into a silicon hose replacement.
Last edited by mtnman82; Jan 11, 2008 at 09:48 PM.
As you can see from the photos, we removed the airbox, disconnected the intake. The red circle shows where the hose connects to. The hose is about 7 inches in length... It's an easy fix, once you reach it. You will need pliers with a long nose. The hose clamps onto the supercharger (where the red circle is).
Last edited by aolsen; Feb 2, 2008 at 12:03 AM.
Perhaps I should replace as many hoses as I can with silicone hoses. Have you guys checked your cam sensors as well? I have to do it soon...
1) The hose isn't really that strong.
2) The factory clamp seems as if it was "made" to eat through the hose, causing it to eventually fail.
Guys, please remember one thing about this hose:
Mercedes made it with different diameters on each end. The end that connects to the supercharger is larger than the opposite end. So, if you used a regular rubber hose, with both ends being the same diameter, it will not fit correctly.
We saved an undamaged piece of the original hose, and stuck it in one end of the new hose (which my dad bought for $3, it's just a regular fuel line hose). It fit perfectly, and allowed us to use the new hose without a problem.


