C63 amg misfiring
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c63 amg
C63 amg misfiring
Gents, need some advice . I recently had redone my exhaust and software tuning . We tested it and ran with pump gas and everything was looking good. No issues . We had a drag event so I did as I usually do. Filled up with a race mix on the morning whilst going to the track . 10 km on running , my engine light flickers yellow and the car started misfiring and also idling high and then low. We plugged in the dashdaq diagnostics when I got to the track and it showed misfire on cylinder 8. We cleared the code and car was perfect for 1 run and thereafter the engine light back on and now misfire on cylinder 6,7 and 8. I ran the fuel out and filled up with normal pump gas and after a few km , the misfiring again. I don't know if it was the fuel since that was the only thing changed, however why didn't the problem now go away when I put normal pump gas. I ran race mixed fuel before and had no problem . Any ideas or suggestion .
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Joined: Aug 2008
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From: South Africa
2008 C63 AMG
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Joined: Jul 2012
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From: Canada
07 E63 + 07 CLK63CAB
Well you have done 3 things, exhaust, software tune and then changed the fuel.
Pull the plugs probably original and should show signs lean, rich, gap not right, burnt tip.
Go back to the tune and look for the answer there.
Pull the plugs probably original and should show signs lean, rich, gap not right, burnt tip.
Go back to the tune and look for the answer there.
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Senior Member
Joined: Aug 2008
Posts: 272
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From: South Africa
2008 C63 AMG
Time: Sat Aug 23 08:16:23 2014
Reading Codes:
Mil Status is ON
1 DTCs
P0308: Cylinder 8 Misfire Detected
0 Pending DTCs
End of operation.
Time: Sat Aug 23 08:16:23 2014
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Joined: Jul 2013
Posts: 118
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GTR R35 1300whp, C63 Weistec stage 3
Possible causes
- Faulty spark plug
- Clogged or faulty fuel injector
- Faulty ignition coil
- Fuel injector harness is open or shorted
- Fuel injector circuit poor electrical connection
- Ignition coil harness is open or shorted
- Ignition coil circuit poor electrical connection
- Insufficient cylinder compression
- Incorrect fuel pressure
- Intake air leak
http://engine-codes.com/p0308.html
- Faulty spark plug
- Clogged or faulty fuel injector
- Faulty ignition coil
- Fuel injector harness is open or shorted
- Fuel injector circuit poor electrical connection
- Ignition coil harness is open or shorted
- Ignition coil circuit poor electrical connection
- Insufficient cylinder compression
- Incorrect fuel pressure
- Intake air leak
http://engine-codes.com/p0308.html
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2010 E63 AMG
I have the same issue of misfires on cylinders 6, 7 and 8. Car drove perfect to work and then started it up and instantly had the bad idle and drove bad.
I took it straight to the dealer and got service B performed at 77K miles and had them check on what is causing the bad idle/limp mode. The tech said compression is good, swapped coils and that did nothing.
He also unplugged the MAF sensor on the driver side (left) and I did as well and the car idles and drives like normal. I swapped MAF's and still get the misfire on 6, 7 and 8 so that rules out the MAF.
Should I try new spark plugs? Not sure if I need to change O2's since I did not get any faults regarding this and I have a Eurocharged tune ignoring the readings.
Thx
2010 E63 with the following MODs:
- ROW air box
- Eurocharged V5 tune
- MBH LT Headers with X-pipe and cat deletes
I took it straight to the dealer and got service B performed at 77K miles and had them check on what is causing the bad idle/limp mode. The tech said compression is good, swapped coils and that did nothing.
He also unplugged the MAF sensor on the driver side (left) and I did as well and the car idles and drives like normal. I swapped MAF's and still get the misfire on 6, 7 and 8 so that rules out the MAF.
Should I try new spark plugs? Not sure if I need to change O2's since I did not get any faults regarding this and I have a Eurocharged tune ignoring the readings.
Thx
2010 E63 with the following MODs:
- ROW air box
- Eurocharged V5 tune
- MBH LT Headers with X-pipe and cat deletes
Junior Member
Joined: Apr 2009
Posts: 63
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2010 E63 AMG
Do you happen to know the primary 02 sensor part numbers for both sides? Made by bosch I assume.
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2008 C63
