Misfire Issue, Can't Diagnose
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CLS550
Misfire Issue, Can't Diagnose
Hello MBWorld members.
First time posting here, long time lurker for other repairs I have done on Mercs. Anyways, onto my issue.
I am currently having cylinder misfire issues. I have the following codes:
P0300
P0306
P227D
P2540
P0308
P222D
I am pretty sure the P227D and P222D codes are just because I have been starting the car without the airboxes plugged in, since I want to verify the missfire issues quickly without having to take them on and off. Could be wrong, though, of course.
Here is what we have already attempted (keep in mind the errors stay on the same cylinders after each of the following attempts):
Moving the plugs
Moving the coils
Driving for a bit
Clearing codes
The current working theory we have is that the coils were really stuck when we were taking them out of the car, as a result, I had to buy a new set after breaking most of them. That's fine, but we currently think that since I was pushing on the wiring harness alot to get the coils off, I may have damaged a wire. We have now bought a power probe, but we also have a multimeter.
My question is, what do you guys think we should do next, and how do we do it? A local repair shop we frequent got us a wiring diagram, so we are set on that front, but frankly, electronics are a bit over my head, and I feel like a fish out of water.
Thanks in advance, and sorry if someone else has made a post already about this.
First time posting here, long time lurker for other repairs I have done on Mercs. Anyways, onto my issue.
I am currently having cylinder misfire issues. I have the following codes:
P0300
P0306
P227D
P2540
P0308
P222D
I am pretty sure the P227D and P222D codes are just because I have been starting the car without the airboxes plugged in, since I want to verify the missfire issues quickly without having to take them on and off. Could be wrong, though, of course.
Here is what we have already attempted (keep in mind the errors stay on the same cylinders after each of the following attempts):
Moving the plugs
Moving the coils
Driving for a bit
Clearing codes
The current working theory we have is that the coils were really stuck when we were taking them out of the car, as a result, I had to buy a new set after breaking most of them. That's fine, but we currently think that since I was pushing on the wiring harness alot to get the coils off, I may have damaged a wire. We have now bought a power probe, but we also have a multimeter.
My question is, what do you guys think we should do next, and how do we do it? A local repair shop we frequent got us a wiring diagram, so we are set on that front, but frankly, electronics are a bit over my head, and I feel like a fish out of water.
Thanks in advance, and sorry if someone else has made a post already about this.
