2004 Disco, with 60,099 miles: Last week, received flashing "Service Engine Soon". Truck became sluggish. Receives CODES: P0300 (Random multiple cylinder missfire), P1300 (Manufacturer specific DTC), P1301 (Cylinder 1 missfire), P1306 (Cylinder 6 missfire).

After searching on net and posting on this forum, concluded that I needed to change plugs & wires. After replaced, the truck still runs very rough and received more codes: P0300 (Random multiple cylinder missfire), P0300 (Cylinder 1 missfire), P0306 (Cylinder 6 missfire), P1300 (Manufacturer specific DTC), P0301/P0306, & P0304 (Cylinder 4 missfire), P0303 (Cylinder 3 missfire).

Any advise on what else I need to check? Please help.

 

What brand plug wires did you use?

 

Champions Spike555.

 

Champion plug wires? I have not heard of them, obviously I have heard of Champion spark plugs.
But you need new plug wires. You MUST use either Land Rover plug wires or Magnecor plug wires.
Anything else and you will be doing the job again.
www.atlanticbritish.com
It sucks, but that is the hard core fact, no other plug wire holds up, I dont know why, but thats the way it is.

 

My bad... I had taken the cheaper route and ordered STI.

 

Even brand new, they will not work?

 

So you used Chamion plugs and STI plug wires. Is that right?

And yes, even brand new some plug wires will not work on a Land Rover.
The Magnecors come with a lifetime warrenty, the LR ones do not.
They are about the same price, get the Magnecors.

 

Awe man...... Thanks Spike555. I will have to redo it.

 

Sorry man, I know it is a PIA with a DII too.
Good news is that you can return your STI wires for a refund.

 

I would highly recommend plugs other than champions, i personally do not get a long life from those or autolites in any of my vehicles. I have found NGK plugs cost about the same as champions or autolits but i get better luck from them. But im sure some one might have a better type that they know works better.