Check Engine: P21A3 Cylinder 8 Air-Fuel Ratio Imbalance
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From: DC Metro Area
2015 S550
Check Engine: P21A3 Cylinder 8 Air-Fuel Ratio Imbalance
A few months ago I started getting the following check engine error code on my 2015 W222:
I called my MB dealer and told them about the codes after they serviced the vehicle. They suggested I bring it back and let them replace the fuel injectors. Now I'm a little skeptical because it seems either the dealer isn't sure about the cause of the codes or they're trying to get more money out of me. Does anyone have any thoughts on how to resolve the P21A3 code or what may be causing the random misfire codes?
P21A3 Cylinder 8 Air-Fuel Ratio Imbalance
A few weeks ago I started the car and received the following check engine error codes:Confirmed
P0300 Random/Multiple Cylinder Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0306 Cylinder 6 Misfire Detected
P0300 Random/Multiple Cylinder Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0306 Cylinder 6 Misfire Detected
4 Pending Trouble Codes
P0300 Random/Multiple Cylinder Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0306 Cylinder 6 Misfire Detected
P0308 Cylinder 8 Misfire Detected
I turned the vehicle off, restarted it and it appeared to be fine. I later took the vehicle to my local MB Dealer and they said I need to replace all 8 ignition coils and 8 spark plugs. I authorized the replacement at a cost of $2,750.00. I picked up the vehicle and there were no problems. The car sat the next day until I went to drive it that night. When I started the car that night, the check engine light came on with the exact same check engine misfire codes. I turned the vehicle off, cleared the codes and restarted it. It seemed to be fine with the exception of the P21A3 Cylinder 8 Air-Fuel Ratio Imbalance code which keeps coming back.P0300 Random/Multiple Cylinder Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0306 Cylinder 6 Misfire Detected
P0308 Cylinder 8 Misfire Detected
I called my MB dealer and told them about the codes after they serviced the vehicle. They suggested I bring it back and let them replace the fuel injectors. Now I'm a little skeptical because it seems either the dealer isn't sure about the cause of the codes or they're trying to get more money out of me. Does anyone have any thoughts on how to resolve the P21A3 code or what may be causing the random misfire codes?
