03'55AMG

For those who saw my fourth of July burnout video (seen here: https://mbworld.org/forums/w211-amg/...ou-have-e.html), my issue is a result from this. Shortly after the burnout, the car developed a misfire/dead miss. (Video of misfire will be at bottom of thread) There were no noises, or sound of anything breaking, or any sounds that aren't normal. Just a slight miss. So I quickly put it in the garage and noticed there was no CEL before I shut it off. I figured it was an electronic gremlin, so I unplugged the negative battery terminal; and let it sit over night.

The following day (fifth of July), I plugged it back in and proceeded to re-sync all the windows and sunroof. Then I started it and the same miss from after the burnout was present. I then contacted Shardul to get an opinion, and he suggested I do a compression test. So I followed his advice, and all cylinders gave strong readings. Lowest PSI found was 158, and highest was 161 PSI. Overall they were almost all dead on 160 PSI. I then breathed a huge sigh of relief, as I was thinking I killed some piston rings (and because of my high oil change interval that showed metal contents in a lab reading). At this point the car only stored a CEL for the CPS I unplugged to test compression.

I then proceeded to make sure all connections were tight, and that there were no vacuum leaks. Everything checked out. Shardul then suggested I drive the car until a CEL stores, which worked. STAR pulled two codes from engine electronics for Misfire detected, and Cylinder 1 misfire. Freeze frame data showed both stored at the same time, while the car was at a stop (red light/stop sign etc). So I then cleared the codes, and put it back together until I could find more time to tinker with it, which was earlier tonight.

Other things that may help diagnose this issue are:
1: The spark plugs were wet with gasoline and the exhaust smells very rich.
2: I picked up a new set of plugs to see if I fouled one of mine, but haven't installed them yet. If that doesn't do it, I will move coil packs around and see if the misfire follows the coil pack or stays on #1.

Can anyone here give me some advise on how to proceed (besides new plugs, moving cyl #1 coil pack and no more burnouts )? I have a STAR setup if it helps.

Here's a video of the misfire. It is much more obvious in person. The video didn't capture the sound too well because of the resonance in my garage.
http://s1098.photobucket.com/user/Jo...75c71.mp4.html

Here again is the burnout that led to this.
http://s1098.photobucket.com/user/Jo...69ea3.mp4.html

Sorry for the long post, but this misfire is driving me nuts!

DonnieD

The coils are known to fail.

SPatykAMG

You can test the coil with an ohm meter and should be able to find the exact specs in stars

03'55AMG

Good call. I wonder if it isn't like most where you should see between 5K and 7K ohms. I will check it out tonight!

SPatykAMG

Should be similar but you need to test both primary and secondary on the coil. star should walk you through all that. also for reference a replacement coil from Autozone is $100, pn C1361

03'55AMG

Here are some pictures of the CEL codes, the freeze frame for each code, and some other helpful information.
Codes:

Misfire freeze frame:



Possible causes for misfires:

STAR coil pack test procedures:


Then I thought I would show this one to you guys, Possible causes for high fuel consumption.. I added two things Mercedes forgot to mention...


I will update when I get the results from the coil pack testing!

03'55AMG

I tested the coils, and they all checked out. BUT, I am almost certain I found the root problem here. Notice below where it lists CPS and a cause for misfire.
Well, today I was going to move the car into my big bay to remove the bumper and do other things I have been putting off, and here was the result. The car started throwing out weird lights, and would not start. It displayed an SRS malfunction, ESP malfunction, SBC STOP VEHICLE NOW malfunction in blood red, and then the others show in the video (the two maintenance lights are impossible to clear for some reason, help on that?).
http://s1098.photobucket.com/user/Jo...6fb57.mp4.html
So I used this as a reason to stock up on some parts for the beast, as well as some extra random parts I needed. Hopefully the car will be fine after the repairs! Just have to wait and see.

Nissanskies08

What ended up being the cause of the misfire, gas soaked plugs and the random lights on start up?

210lvr

99% of the time, a misfire on 112/113 is due to worn ignition wires. coil packs are rare. use the smooth engine running section to watch the cylinders. if you get a random mis on 1, swap in 2 known good wires or swap the entire coil pack with wires to another cylinder. it really is that simple most of the time.

Critter

Any idea why the gas pump (low level) light is on it looked like you had over 1/4 tank full?
Check for fuel pressure at the schrader valve on the fuel rail.