Supercharger kicking out?
Has anyone ever had this happen? It's all electronic and no codes are being thrown. I checked codes and there was a pending misfire code on cylinder 8, but I have no idea how old that code was.
IAT's are relatively low as well. It's cold here in Wisconsin...and IAT's were in the 50-70 degree Fahrenheit range. I do have an upgraded CM30 pump anyway.
HELP!
Last edited by kjlindgr; Feb 6, 2010 at 05:11 PM.
It's definitely something electrical/computer driven. The weird thing is that when the car is cold, it acts fine. Once it warms up, it seems like it gets worse and the S/C disengagement happens much quicker post restart. Very confusing.
Keep the ideas coming guys!
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I'll try to hard-wire the pump and look into the IC system split more to see if that's my issue.
NINJA EDIT: You can't/don't bleed the coolant system in these cars, do you?
Last edited by kjlindgr; Feb 7, 2010 at 11:47 AM.
Thanks for the help guys. You are definitely the best
Could the car be cutting the S/C when it senses a misfire? I've got brand spankin' new plugs in it but old wires (54K miles). I can certainly get new wires and probably should.
The new I/C failure idea that has come to light makes me curious too though. One item of info on that. The car was cold-cold, went for a spin and I got the S/C to lock out even before the car hit 60 degrees Celsius. The lack of flow makes me wonder though if it's going out. This fking pump only has about 1500 miles on it though. Ugh. Any better ones out there?
Last edited by kjlindgr; Feb 8, 2010 at 12:10 AM.

I'm starting to think I should chase the misfiring issue though now since one seems to directly follow the other (misfiring codes then bad engine running). Here are my next steps, please everyone give me your input:
1. Repeat issue to see if there is a pattern with particular cylinders impacted. I have a hard time believing that 4-5 cylinders developed this issue all of a sudden, but whatever.
2. If I can repeat it on cylinders, swap plug wires and eventually coil packs around to see if I can move the issue and isolate it to plug wires.
3. Purge the fuel rail to make sure that there is no trapped air. I can't believe there is any though. Gasoline has a couple cans of seafoam in it to hopefully clean things out as well.
4. Get a fuel pressure gauge and see if it's a pump pressure failure issue.
5. ???
I did some searching and found that some was attributed to bad cats plugging up the exhaust flow. These cats are brand new...literally 20 miles on them...so that's not the problem.
Thoughts? Anyone else have this issue?
https://mbworld.org/forums/w211-amg/...er-issues.html
Plug wires and coils could be the culprit...but it's hard for me to think that multiple ones could all go at the same time. That just seems way odd to me.
I can also check gaskets again. I did pull the supercharger recently so the upper and lower intake manifold gaskets were taken out. I sprayed them with copper gasket spray and reused them. It idles good which to me would indicate they are sealing fine, but maybe they are leaking a little...I dunno.
That at least gives me a place to start again tonight.
Plug wires and coils could be the culprit...but it's hard for me to think that multiple ones could all go at the same time. That just seems way odd to me.
I can also check gaskets again. I did pull the supercharger recently so the upper and lower intake manifold gaskets were taken out. I sprayed them with copper gasket spray and reused them. It idles good which to me would indicate they are sealing fine, but maybe they are leaking a little...I dunno.
That at least gives me a place to start again tonight.
Misfires in multiple cylinders that occur together is likely and indication of an air leak, not a 100% thing but def check for that.
Anywho, did some more diagnosing today. Not sure I accomplished anything, but I did get a pattern forming. When it cuts out, it typically throws 5 codes...misfire on cylinders 5, 6, 7, 8, and a "random misfire" P0300 code. Seems like it's cutting off that whole bank of cylinders for some reason.
Anyone know what would make it kill an entire side? I have a hard time believing this is all just random and that it just so happen to have a bunch of plug wires go bad and they just so happen to all be on the same side. That makes no sense.
The side that's wrong is the driver's side too and you can't mix the coil pack wires around on that side. The passenger side is different, but cylinder #1 is numbered.
Still at it I guess...
Last edited by kjlindgr; Feb 8, 2010 at 10:18 PM.


