Rokas

I figured out the cause of my p0300 misfire code in my 96 LS400 with 210k miles. I was changing the spark plugs when one of the wires came apart as I was pulling it out. Seems like someone broke it.

You know the plastic holder that slides onto the spark plug? The wire comes out of it. It has somehow ripped. There IS some free wire and there is some contact when I shove it back in there.

Enough that the car doesn't even shake anymore and it misfires pretty rarely. Overall the car is driving OK for now.

Of course I'm waiting for the car at the junkyard to get the wire but there hasn't been one in over a month. Does anybody have that one? I'll happily pay for it. I don't want to buy all new wires.

What's messed up is I had my old set but I just can't find it.

Another question. If I shove copper wire in there to give it even more contact, would that help? I just want to change the damn wire but who knows how long until I find just one.

Do any other cars use the same exact wires? Can I modify it to work? I have a couple of those wires that don't connect to spark plugs but rather from the distributor cap to something else - I forget - so they don't have the same housing but if the wire works, I can possibly connect it to the spark plug just like that and plug it it but I don't know if that's even a good idea. The wires I'm talking about here are part of the distributor wires - they just don't connect to spark plugs, to reiterate, so they're different.

If anyone is in Orlando or wants to sell me one wire, PM me. Mods please delete this comment if it's against the rules.

Michael88

If I understand correctly, then you accidentally pulled the boot off the plug wire. This has happened to a lot of people. From my experience this is a sure indicator that is time for a new set of wires. Be sure to use boot grease inside before installing new wires. Around here they have it in a small pouch next to the register at the auto parts store. Cost about a $1.00. If you don't use it, you may be in the same situation at the next tune up. As far as jury rigging an old spark plug wire, I would only do this in a dire situation like having to walk 5 miles to the next town. Be that as it may, the important thing to remember is that the an uninsulated wire does more than transfer spark to the spark plug. It will send sparks to the engine block, too. That is why they have deep thick boots to shroud the entire plug. So, if you have torn the wire from the grommet that attaches to the plug, you will need to crimp it back on, electrical tape it (maybe), and then slip the boot back over all that before placing it on the plug. Quite difficult to do, because the stiffness of a good condition wire/boot is what allows you to fit it on the plug. A jury rig as described would be like throwing darts at it and hoping the grommet slips on the plug.

Rokas

Sorry for the bad description, but it just came out of the boot. At the bottom of the boot I could see metal so I shoved the exposed wire in there and connected it to the spark plug with the complete boot.

Well, I finally found my old wires. I assume it's ok to replace just one? Is that a potential problem?

Michael88

I would totally replace it with an old wire rather than a damaged wire with the condition of getting a new set and boot grease very soon.