2009 e550 4Matic misfiring
#1
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Thread Starter
2009 e550 4Matic misfiring
I changed my spark plugs with Bosch double platinum as oem ones that was in before and I change my coil packs but I知 getting codes p0300 p0301 p0303 and p0304 my car is straight piped but I had put back my 02 sensors back in my exhaust can it make my car miss fire from sending bad reading to the ECM and it only miss fire wen the car is cold once warm up and I drive it nomore miss fire I知 lost
#2
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MY'14 W212 M276 3.5NA @60kMi
O2 delete...
I changed my spark plugs with Bosch double platinum as oem ones that was in before and I change my coil packs but I知 getting codes p0300 p0301 p0303 and p0304 my car is straight piped but I had put back my 02 sensors back in my exhaust can it make my car miss fire from sending bad reading to the ECM and it only miss fire wen the car is cold once warm up and I drive it nomore miss fire I知 lost
The ECU directly measures and learn from upstream O2 how clean is the engine combustion. From the fuel map the long-term fuel trims used to calculate timings of gas injection.
When the combustion is poor, the trim is negative and you get lean misfires specially cold when the engine needs rich mixtures.
WOT should not be affected by conventional fuel metering.
#3
Member
Thread Starter
Yes, you've got it
The ECU directly measures and learn from upstream O2 how clean is the engine combustion. From the fuel map the long-term fuel trims used to calculate timings of gas injection.
When the combustion is poor, the trim is negative and you get lean misfires specially cold when the engine needs rich mixtures.
WOT should not be affected by conventional fuel metering.
The ECU directly measures and learn from upstream O2 how clean is the engine combustion. From the fuel map the long-term fuel trims used to calculate timings of gas injection.
When the combustion is poor, the trim is negative and you get lean misfires specially cold when the engine needs rich mixtures.
WOT should not be affected by conventional fuel metering.