nc1wynot

So, I changed the coil, the plugs and I still seem to get the code for #2 misfire. The injector and compression test is next. I've been searching on here but can't seem to find any DIY for changing out an injector. Any assistance would be greatly appreciated.

It looks like I'm going to have to remove the airbox...of course

But after that I don't really know the process. Any help?

Thanks in advance.

- Steve

ontmiss

Can this help?

nc1wynot

ontmiss...You Are The Man!

Thank you so much. I'll be doing a DIY with images using this.

- Steve

ontmiss

Get 1 case of before you start.

casper_c230

I opened the file and, "Risk of explosion" sorta scares me. Glad a member was nice enough to post though.

C230 Sport Coup

This isn't the 12 dollar hose issue, or something to do with the head like other
people have? Yeah, I know it's a 2005, but I'd check the compression.
If it's not even, I'd blow some seafoam through it to clean the carbon off.
Did you switch up the coilpacks to see if the problem moved?

nc1wynot

I changed the coils around and it was still just #2 cylinder misfire. I replaced the coil and the plugs as well. The CEL went away for a day and then came back. I put some techron in and it went away for another day, but then came back again. I'm not sure if it is the $12 hose but I'm going to call the dealer to see if it was already changed out. Thats a campaign issue, right? If it hasnt been done, I'll just have them do it.
The stealer told me it was probably an injector. Hopefully its not compression. That will be my next step if replacing the injector doesnt work.
I heard about this "seafoam" stuff. How do you "blow some through it"? I heard a few good things about it but then others say stay away from it....I'm torn...LOL.
Its only got 36k miles on it so Im hoping its not the compression. That would be pretty sad for a MB.
I keep getting the same statement when I talk to a stealer about how much they charge for parts/repairs..." well, IT IS a Mercedes..." OK, well my statement back is..."yea, it is, with ONLY 36k miles on it".

I probably wont get the injector until next week sometime (in Hawaii) so when I'm under the airbox I'll check that $12 hose too.

This weekend = Transmission filter/fluid change, steering fluid flush

- Steve

nc1wynot

So, I took the air box off to make sure it wasnt the "$12 HOSE" and it looks like a brand new one was put on by the dealer (I didnt trust them so I checked). I am about to change out the injector but was wondering,
where do you put the Seafoam to "blow it out"? I put about 1/2 a can in the fuel tank but was wondering if putting it in somewhere else?

Thanks for all the help. I'll be taking notes/images and posting a DIY for other members in the future. I want to do the compression test but it seems in Hawaii everything cost an arm and a leg. I fear how much its gonna cost for a damn compression tester.

- Steve

amanonfire

A compression test should only cost an hour labour at any shop.

nc1wynot

The optimum word is "Should"

Hawaii seems to be different then any other place I have lived. Even Bahrain was cheaper than Hawaii. Its really rediculous here.

Anyway, thanks.

- Steve

davidtom

Ohtmiss,
I have a problem with p171. I did the same thing like others did to call the dealer to check if the $12 hose got already repair on my 2005 c230. They said it done last year. I took it to my local shop to have they check, they found out 2 breather hoses and its check valve leaked. They showed me the collapsed parts before replacing. After they got the job done, they tested drive, and called me the Mass air sensor was also bad that set the light back on. I approved $450 part. They replaced and installed the new one. I picked it up, drove home but the light set back on after 15 miles from the shop. Took it back to have they look at it again. Defective sensor got replacement. They kept the car for 2 days to test. This moring they called to let me know there must be something wrong with the computer. Since they tested its emission, its result was gross polluter with both high HC and Co. They qouted the computer from dealer $2500. I got really upset and decided to get the car back to sell as is. Drove home, the car seem very smooth. I opened the hood to check what they had lately done to my car, I found couple disconnected air hoses hanging around the exhaust side. I saw the hoses ran from the valve on top engine to ? (where I don't know). Can you give me the picture showing where the hoses go to?
Truly thanks for your great help.

ontmiss

Not sure what hoses you are looking for but here is some oics of engine

nc1wynot

Man, that shop ripped you off. The MAF only cost me about $170 and you could have done it yourself.
As far as the hose your talking about...I bet they forgot to reattach the hose coming from the top of the engine, towards the MAF. It connects to a round fitting after the MAF. Just follow the hose down past the MAF. There is a connection that the hose just slides over. If its a rubber collapsible hose, thats the one. I almost forgot to reconnect it today when doing the injectors.

Just to let you know, Most people that I know...Have gotten the same codes as I have and it ended up being the injectors. Some changed out all the injectors and never had an issue again, well until the suspension problems started....LOL.
What codes are you getting and I could possibly help you out. Ive done everything from change out the MAF, the coils, the plugs, add seafoam, and now changed out the injector.

- Steve

davidtom

Ontmiss,
Thank you for your upload pics, I saw the hoses connecting from the black switch (valve?) under the engine cover to the metal valve in the 2nd pic but not sure which hose goes to which port. Can you instruct me, please?

Nc1wynot,
Thanks for you offer to help me out. The code printed out on my invoice receipt was p0171. I don't know how to repair it myself, and have no knowledge how to pull things out and put back in order good like you. All I need is to put the hoses back in place, then I can post to sell as is. It is not worth to spend more money in this car anymore.

nc1wynot

david - that code seems to be your running to rich. Sounds like the MAF to me but I'm no pro. Search around the site to talk to some pros.

Well, I changed out the injector and after a week the CEL cam back on. I am at the end of the rope. The compression test came out fine. I'm not sure what else it could be. The CEL only comes on if I end up sitting at a light for to long or sit in park running for more than 5-10 minutes. I get the same code, "misfire #2 cylinder"

Not to sure what to do next. Does anyone know How/where you put that Seafoam in to clean the engine? Can that be put in the engine? I ran some through the gas tank/fuel system already. The car seems to run fine until I get that damn misfire. I clear it out, and it runs great again.

Any ideas would be greatly appreciated. Thanks in advance.

- Steve

Glyn M Ruck

We are running out of options. Did you replace the fuel filter with a genuine Mahle Knegt? The fuel pressure regulator is built into the filter. We have had trouble lately with aftermarket fuel filters on the forum.

You need to check your fuel pressure.

nc1wynot

Kind of weird though it would only effect 1 cylinder. I'll check it out with another filter.
Things a pain in the butt now...LOL.

- Steve

Glyn M Ruck

See this thread - You might have the start of d1no's troubles.

https://mbworld.org/forums/c-class-w...ard-start.html

nc1wynot

Hey Glyn -

I don't think thats it but I'll check with another filter. I replaced it with an OEM filter but who knows. The car starts fine. just after running for a bit, idling it starts running rough and get CEL. The funny thing is, it doesnt happen all the time.

So Frustrating!

LILBENZ230

Have you tried cleaning the throttle body? Rough idles.. I know it's a stretch but as Glyn said the options are limited.

Glyn M Ruck

Yep - MAF is clean, clean throttle body. Measure fuel pressure. If one injector is slightly down, low fuel pressure can give you the odd misfire on that cylinder.

The next thing is going to be checking the engine harness. Have you had oil leaks from the cam sensors into the harness?

nc1wynot

Hey Glyn and LIL,

I just got my hands on a Innova diagnostic tool with a little better explanation to my problem.
Here is what it says:
Parameter Description Value
DTC for which Freeze Frame was Stored P0302
Fuel System 1 Status Closed Loop - fault with at least one oxygen sensor
Fuel System 2 Status Not Supported
Calculated LOAD Value 41.18 %
Engine Coolant Temp 154.40 °F
Short Term Fuel Trim - Bank 11.56 %
Long Term Fuel Trim - Bank 10.00 %
Intake Manifold Absolute Pressure 26.35 inHg
Engine RPM 2,447.00 rpm
Vehicle Speed Sensor 20.51 mph
Absolute Throttle Position 29.41 %

My question is...obviously its saying there is an O2 sensor thats bad, right? which sensor is it? and how would I go about changing that.

If thats not it, I am clueless....LOL.
Thanks again guys!

- Steve

nc1wynot

Man, this thing is so frustrating!
I changed out the injector and i got no CEL for a few weeks.
It seems it only runs rough and gets a CEL when I turn the A/c or vent fan on. I'm not sure what this could mean. It runs great until i turn the fan on...then i get rough idle, CEL and codes for thermastat & #2 cylinder misfire.

ANY IDEAS guys? Thanks again!

dpgeek

Your problem is EXACTLY the same as I'm having and I have read through your issues in this forum. I have an 05 C230, 34K Miles, P0302 that won't go away, shows up when I turn on AC too, then I get rough idle also. Changed my plugs, changed my coil pack. However, I have not changed fuel injector, I THINK i had the $12 hose fixed, not sure. I feel your pain bro!! One day car runs fine, another it's rough. It's been like this about 4 months. I hope no long term damage is done while driving it in this condition.

Glyn M Ruck

Change the upstream O2 sensor. O2 sensors cycling too slowly can cause engine stumble.