I have a 2003 Land Rover Discovery and have a code 4b Catalyst damaging misfire multiple cylinders .
3f Catalyst damaging misfire cylinder 1
41 Catalyst damaging misfire cylinder 3
43 Catalyst damaging misfire cylinder 5
45 Catalyst damaging misfire cylinder 7
I have replaced the crankshaft sensor ( because it stopped ) air flow sensor ( I was told that was the problem ) the camshaft censor ( because I was down there so why not )
head gaskets ( because it was overheating ) replaced the lifters ( because there was a taping noise , did not like that ) fuel pump pressure is according to factory specks . both heads have a fresh valve job , I tried a injector cleaner that made no difference , the Rover runs fine where you would not think that there is anything wrong with it , the next time you take it out about 10 miles down the road , it will start to miss very faint but still very drivable , It does not stall at lights or stop will take hard excel oration no missing just a hard pull . If some one could help me with this problem I would be very thankful Paul
3f Catalyst damaging misfire cylinder 1
41 Catalyst damaging misfire cylinder 3
43 Catalyst damaging misfire cylinder 5
45 Catalyst damaging misfire cylinder 7
I have replaced the crankshaft sensor ( because it stopped ) air flow sensor ( I was told that was the problem ) the camshaft censor ( because I was down there so why not )
head gaskets ( because it was overheating ) replaced the lifters ( because there was a taping noise , did not like that ) fuel pump pressure is according to factory specks . both heads have a fresh valve job , I tried a injector cleaner that made no difference , the Rover runs fine where you would not think that there is anything wrong with it , the next time you take it out about 10 miles down the road , it will start to miss very faint but still very drivable , It does not stall at lights or stop will take hard excel oration no missing just a hard pull . If some one could help me with this problem I would be very thankful Paul