2003 Land Rover Discovery

My Rover

New Member
Joined
Jul 13, 2022
Posts
2
Reaction score
0
Location
Canada
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
 

joey

Custom Rover Accessories
Staff member
Joined
Jun 28, 2004
Posts
10,409
Reaction score
158
If I were to guess (keep in mind hard to diagnose some issue without seeing a vehicle) I would say you have a bad coil pack. One pack does odds, one does evens.
 

My Rover

New Member
Joined
Jul 13, 2022
Posts
2
Reaction score
0
Location
Canada
That is what I thought but I like to get other Land Rover pros. ideas , thanks for the information Thank you for the help
 

Scanachi

Well-Known Member
Joined
Nov 14, 2011
Posts
54
Reaction score
5
Location
Ohio
This was my guess, too.
Please update us when you’ve got it diagnosed/repaired.
 

Latest posts

Forum statistics

Threads
35,409
Posts
208,392
Members
29,706
Latest member
Schildy
Top