Hello Everyone,

I have a 2000 Land Rover Discovery Series II with the Bosch 4.0 engine.
The engine light is on and flashes, and I have had it checked and the codes are: Multiple cylinder Misfires, cylinder 2 misfire, and cylinder 3 misfire. First thing I have done is change out the plugs, they were all in very bad shape, though the ones for 2 and 3 were burned. They were so far gone you could drive a semi through the gap! I used OEM Champions as replacement. At this point I did not replace the wires yet. I got a lot of my power back, and the idling seemed to be better. Codes were cleared. Now the same problem has come back after about half an hour of driving. Same codes as before. I plan on replacing the wires with the magnecor 8mm wires. I plan on doing this without removing the IM as I have found the instructions on how to do it through this forum. Also it should be noted I do not have secondary air.

If I have the same problem still after this is done, I will be replacing the coil packs. My question is: If after replacing wires and coil pack, I still get the same problem, is there something else I should be checking that would be something I could check/possibly replace without special tools? Also my gas mileage has gone down a lot. I was getting a hair under 400 miles to a full tank using 93 octane. I am now getting barely 200 miles to a full tank. I am pretty sure this is because I am only running on 6 out of 8 cylinders.
Air filter is fine, and am wondering if I solve the misfire problem if that will fix my mileage problem.



Thank you for any help in this matter.

 

I'm betting the wires will fix your problem. I would not drive it with it misfiring that bad you can kill your cats.

 

Thanks, I'll be back with an update when I am able to do it, unfortunately I have to wait until a week from this coming friday before I will have money for the wires.

 

Check out apexperformance.net for the plug wires. They had the best price for the 8mm. You do scrape your hands up a tad, but very doable.

Good luck

 

Thanks for the info!

 

And kudos for a great first-post-on-thread, BTW.

 

If you lights start flashing, you must quit driving it or you will cause more damage, like the cats and you will need to replace the plugs again.

 

You are not loosing any coolant are you? If the new wires do not fix you misfire, it could be a head gasket issue if you are having to add coolant.

 

The coolant in the reservoir has always ran low since I've had it, and long before this current problem has surfaced. The reservoir never actually empties, it just gets below the max fill line. I have not found or spotted any leaks though.

 

As long as you are not having to add coolant once it gets just below the max fill line then you head gaskets should be fine.
If you overfill it some will leak out of the overflow tube.
Replace your plug wires, if you bad MPG is still there then you need new O2 sensors.