2002 LR Discovery II with 50K miles. My truck was running fine until i went and filled it up with gas. Ten minutes later service engine soon light came on and codes were P1300, 302, and 303. The cylinders are misfiring for some reason but not sure what P1300 is. Weird it happend right after filling up with gas. Anyone have any suggestions. I dont want to just change the sparks and plugs and the P1300 cause a misfire again, or will the new sparks and plugs fix the P1300 code. Any info is helpful. Thanks.

 

What octane gas are you running? Make sure it is 91 or above. P1300 is a random mis-fire.

 

Gas shouldn't cause just 2 cylinders to misfire, I can see how it might cause the 1300 emission misfire.
Yes, plugs and wires might help, I wouldn't replace them though until you pull the plugs from 2 and 3 and compare them to a couple of other plugs, see if there is a color change or if they are wet.
Mike

 

I always use 93 octane. I will check the plugs and let you know. What exactly id the 1300 emission misfire?

 

I also read on here about someone with the same problem. In their post they mentiond the P1300 was a blocked fuel rail causing the misfires. Anyone know more about this?

 

It is nearly impossible to block a 1/2" fuel rail line, I have never heard of that happening. Have you pulled your plugs yet so we can get on with helping you????
Mike

 

I havnt got to it yet. I wanted to do it myself but have been too busy and my mechanic says he cant get to it til Wednesday. Being that Ive never worked on my truck since I've only had it for 5 months, about how much is invloived in changing the plugs and how much time would it take?

 

As an 02, plugs are easy, plug wires are a bear and need to be done, switching to Magnacor 8mm wires.
Mike

 

I thought P1300 code was "catalyst damaging misfire".
Ed

 

yeah, it is. The Equus site was down when I posted.