Hi, My 98 Disco 1 misfire, particularly cylinder #5 (knew that from the code). One day I was looking under the hood with the engine running, I saw that there are small sparks at the coil pack near the #5 position. Seems like coming out of the rubber boot of the wires. However, I inspected the wires and the outside of the coil pack, they seem to be ok (no crack).

Another problem, I suspect that is related to this "spark leak", is that all the lights in the disco would flash sometimes, and sometimes they are normal, seems like they are not getting enough power.

Also, my disco sometimes would have very low idle when first started, or I sometimes have to keep my foot on the gas pedal when it is first started. But immediately after I drive it, it would have no problem with idling for the rest of the drive. It only happens when it is first started and sometimes it will kill itself because of the low rpm (this only happen when first started.)

Please help~ Thank you!

 

Ok, you need to start with a tune up, new spark plugs and wires.
Use only Magnecor plug wires or Land Rover plug wires.
Use any spark plug that you want, Iridium plugs are what I recommend.
As for the low idle, when was the last time that you cleaned the throttle body?
Also what brand/grade of gas are you using?

 

Hi Spike,

New plugs were put in about 3 months ago. So I would not suspect that's coming from the plugs. The wire looks in pretty good condition.

Therefore I suspect the random "spark leak" is that the coil pack is malfunctioning? or maybe there are some small crack at the cap of the coil pack? I don't know.

It seems like the idling thing and the "spark leak" thing are related somehow. but i m not sure. Anyone have similar experience??


I only fill it up with shell v power / premium unleaded.

Thanks for reminding the throttle body, I will look into that, and clean it if needed.

 

The coil pack is rarely the problem when a misfire happens. If your plug wires haven't been changed out for Magnecor they are more than likely your problem. The factory wires have a short life span and the wires you get at most auto parts places will die very quickly.

 

Yeah just like AK said, store brand wires dont last very long.
I used AutoZone wires my first time, lasted a year.
They went bad exactly to the month a year later, under lifetime warranty so I got new ones.
A month later they were bad, changed again, 3 months later they were bad again, try one more time...1 month later, bad.
I bought Kingsbourne plug wires and so far so good, only been 2,000 miles or so so the verdict is still out on them but they were $35 compared to the $100 Magnecore or $120 LR plug wires.

 

might sound odd commin from a dealership guy, but dont use the LR wires. they changed manufacturers and quality is awful now, the plug tip connectors are oversized and the only thing that holds them on is boot tension. my dealership has even started offering aftermarket wires due to the issues with LR quality.

 

That's good to know Roverguy. Not that I would ever use factory wires after having magnecors but at least we know to steer people away from the factory wires.

 

yeah, i wont use them on a car. we stock magnacore 7mm now, all that AB carries