smoknz28

Okay....wow, just getting baffled what's going on here.

Back in the end of 2013, I had the following codes:

- P0015 "B" Camshaft Position -Timing Over-Retarded (Bank 1)
- P0301 Cylinder 1 Misfire
- P0128 Thermostat
- P2190 Too Rich At Idle

All of which I took care of by changing to new thermostat, plugs and replacing one of the camshaft adjuster magnets.

Here we are a few months later and I now have all of these codes thrown:


P0300: Cylinder Misfire Detected Random Cylinders

P0301: Cylinder 1 Misfire Detected

P0302: Cylinder 2 Misfire Detected

P0305: Cylinder 5 Misfire Detected

P2187: Too Lean at Idle Bank 1

P2189: Too Lean at Idle Bank 2


These all seem like there's an issue with my spark plugs and or spark plug coil packs. Four months ago I changed the spark plugs...so I do find it hard to believe the plugs are bad. There is just over 100,000 miles on this engine and about 1,100 miles on the engine since the plugs were replaced.

What are your thoughts out there on this?

Much appreciate all for your help here.

Glyn M Ruck

Please cancel all codes & disconnect the MAF. This forces the ECU on to a default map. See how it runs. Clean MAF ~ might have a bad MAF. Three on plug coil failures together is unlikely.

Misfires could be due to excessively lean mixture.

Also check fuel pressure at the Schrader valve on the front fuel rail. s/b > 3.8bar or 55 psi. might have a clogged fuel filter or poor pump.

This is a M272 V6 ~ Yes? What plug wires did you change. There are no HT wires.

smoknz28

Thank you for the recommendations.

I must update you all on an error in my original post...which I've updated since. I have not replaced spark plug wires (coil packs)....I have only replaced spark plugs. The spark plug wires/coil packs have never been replaced since the vehicle was new (2006). The vehicle is a 2006 C230 Sport.

I'll clear all codes and disconnect the MAF, but what if it runs worse?

How long should I run the vehicle with the MAF disconnected?

If it runs better....then clean the MAF? How does one clean a MAF?

Thanks!

samaritrey

To clean the maf you remove from car and spray with maf cleaner which you can get at your local parts store.

smoknz28

Doh! Easy enough...

Thank you.

samaritrey

Forgot to mention let maf dry completely before reinstalling!!
When you unplug maf leave the filter and everything else in place and you should noticed very quickly how the car is running.

Let us know how it goes!!

smoknz28

Will do....thanks.

smoknz28

Whew!! Okay guys...so sorry it's taken me this long to finally get back on the Benz and I gratefully appreciate your previous responses and hope you can stick with me here in resolving the issue.

So...I have taken the recommendation and removed the MAF and cleaned it with MAF cleaner I purchased from the parts store. The screen was lightly dirty, but all and all...it wasn't bad. No matter, I spent a couple minutes cleaning it up. I also sprayed the contacts (male and female) with contact cleaner and let them dry.

As the parts were drying...I started and ran the engine for about 5 minutes. Let it idle where it stayed around 850-900 RPM. Seemed to hold good. I then raised the RPM about 1500 and held steady with no fluctuation in RPM. I felt the engine was running better with the MAF disconnected, but I didn't take the care for a drive.

I then shut it down and reinstalled the MAF. Started up the engine and I could distinctly hear a difference right away. Thinking it's because the computer had to relearn...I dunno.... At any rate, I let the engine run a bit at idle where it seemed to fluctuate between 800-950. After letting it run at idle for a couple minutes, I brought the RPMs up about 1500 and the RPMs kept fluctuating on me even though I held the throttle steady as I did with the MAF disconnected.

Result...the engine ran worse with the MAF connected.

As pointed out by Glyn...I have not yet tested the fuel rail pressure as I don't have a pressure gauge to test from the Shrader valve. I will replace the fuel filter though regardless as I don't think we've done this in a while...ack!

You guys with me that I should replace the MAF....or?

Thank you all so much!

Glyn M Ruck

Check fuel pressure. If OK looks like you are heading for a new MAF

smoknz28

Thank you Glyn. Do you or anyone have a recommendation for equipment I'll need to check the fuel pressure? I have CarQuest, Advance Auto Parts and Auto Zone closest to me.

samaritrey

I would see if any of them have a fuel pressure tester as a loaner tool

smoknz28

Loaner....good point!

Thank you all. I'll get this tested and will post up results.

AzCamel

Honestly the MAF is not that expensive, so I would just do it because of the mileage. Also have you checked that you put the MAF and air box back correctly? I made this mistake and finally put it back correctly, check that it is seated, put a bit of oil on the rubber to help promote the seal.

smoknz28

Ack, over $300 is expensive to this hombre....but without testing the pressure....it really does seem that the issue is the MAF if the engine is running better with it disconnected.

There are two fuel pressure testers available to me locally.

- Actron CP7818 $44.99
- Actron CP7828 $41.99

smoknz28

Well alrighty then....the CP7828 is for compression testing...

The CP7818 is for testing the fuel...just not on a Mercedes. Go figure....

Glyn M Ruck

Autozone usually have loaners that will do the job.

smoknz28

Thank you. At this point, I want to purchase.

Any ideas what will work?

AzCamel

Bosch MAF for $107 shipped, it is for the 2006-2007 w203 M272


Delphi is cheaper or the more expensive Calderon one is also available, I trust Bosch

AzCamel

http://www.everythingbenz.com/z/part...FY6Rfgodx4EAaw

http://www.partsgeek.com/ss/?make=Me...99&brand=Bosch

blzdout

I literally had those same codes (maybe more misfires though). It's the MAF. I tried replacing mine with an aftermarket cheap one @ first from eBay, it threw those codes. I then bought a used one from eBay that came out of an old e320, same part number as my original, for around $30 bucks, those codes went away & it ran perfect. I went down the same road as you, replaced all my spark plugs like the shops recommended, etc. But nothing. Once I put in the MAF after the aftermarket one, perfect.

smoknz28

Doh! Well, before I saw this post...I did manage to purchase one through a relative, who works for a parts store. I bought a Bosch MAF for $160 new.

I'll install it later today and will let you all know how it goes..

Thanks

smoknz28

Woot...Woot! I can only hope.

I'll be installing a new Bosch MAF later this morning and will advise.

Thank you for confirming you had the same issues and what resolved it.

smoknz28

Ooop, update on my pricing I paid for parts...which actually was better than expected.

MAF (Bosch) = $99.49
Fuel Filter = $34.47
--------------------------
$141.06

Now....I feel better about the purchase. So good I went ahead and ordered the brake pads for all four wheels to get this task out of the way.

Thanks all....I'll install the MAF shortly and take the Benz on a long ride into Washington, D.C. this afternoon and back. That should give me enough data to see if this has resolved my trouble codes.

AzCamel

Good luck, I am still collecting parts myself for a full tune up in 5k miles when I hit 100k. All fluids, all filters, and sparks. Your next purchase needs to be a good scanner that tells you the code and what it means, well worth the $100+ In the long run

smoknz28

Right on....and good luck with your work ahead of you.

I do have a scanner that reads the codes and tells me the description of the code. Bought it from Harbor Freight and has worked great. I can even record data with it.

Thanks.