1999 Misfiring in cold weather
 

I have a 1999 C230 kompressor that once in a while starts misfiring on cold mornings (<50 deg F) when going to accelerate. Check engine light comes on and continues to run rough until I shut off and restart engine. Then it runs smooth until next time. Happening more often now as cooler weather comes.

OBDII reader says PO300 (misfiring), PO302 (random misfiring) and PO130 (O2 sensor Bank1 Sensor1).

Can somebody point me in the right direction for a fix?

Thanks,

I'm guessing mixture-related misfire caused by a bad MAF. If you have over 100K miles, you'll need to replace your O2 sensors anyway, so you may want to do that first to eliminate them as possible culprits.

MAF Replacement
 

The car does have over 130K miles so could be time for new air sensors then.
Is the MAF difficult to replace? How about the other air sensors? Never done one myself.

I would do the O2 sensors first, since they are a 100k maintenance item anyway. You need a special socket, which costs about $10, but then it is a sttraightforward swap out. I used some long extensions to allow me to access the two front ones from the top of the engine, and would be lying if I said replacing all 4 took more than a half hour.

If you still have the problem, check the MAF. It costs about $250 these days, I think. I am not one to throw parts at cars first, but can't think of anything that would cause temp related stumbling except that, they do tend to fail in the 100's, and diagnosis isn't cheap or guaranteed accurate either. You could also just wait a while to see if you get any codes. Replacing the MAF requires no special tools, and is in the intake tube right behind the airfilter.

If you find the MAF has oil on it you need a new PCV valve. With that mileage you should change it anyway from what I have read. Someone recently posted the parts and procedure for that job. My 98 doesn't have it luckily.

Repair Manual or CD Recommendations
 

I have no shop manuals to guide me in repairs on my C230.
Can guys recommend a good shop manual or CDs for this?
Thanks,

Paul

Here's some leads on the manuals: Online Manual or DIY section - Benzworld.org - Mercedes-Benz Discussion Forum

Replacing Oxygen Sensor
 

Any advice on using universal oxygen sensors vs Bosch or the really expensive OE's?

Also, can I remove the sensor first and still drive the car? When it acted up before, I had to drive home in "limp home mode" I guess they call it.

Being able to see my existing one up close may help me decide which replacement model to buy.

Thanks,