Should I change the spark plugs myself?
 

I'm just worried about messing up the wires that connect to the coils. I've seen other people accidentally remove some of the wires from the boot and it was a big mess. Should I just pay to have them done?

There's two kinds of people who work on their cars: those that break something and freak out, or those that break something and just fix it.

If you're going into a situation where you're going to freak out, you might want to consider having it done. If it's not your only car or you're not going to freak out if you break something - do it yourself.

I did mine a few months back. I just took my time and was careful - no issues with wires pulling out of the coil connector.

Lessons learned from those "other people" are that one should not pull on the wires to unplug the connector. Instead, use a pair of long-nose pliers to simultaneously pressing/releasing the latch and grabbing/unplugging the connector. Please note that the plastic latch is likely to be very brittle after years of baking in the engine bay, and can break. If you decide to hire someone to replace your plugs, be sure to inspect each connector (for broken latches) before you pay them.

I've done spark plug swaps on two LS430 both at about 120k miles.The first one went off without a hitch. The second one I pulled one wire on one of the clips, they have 4 wires per clip and the order of wire is different on each clip. Luckily I had just replaced the coil pack clips on my GS300 so I knew what had to be done. It's not a huge deal at all if you're willing to solder the wires. If you want to be more like OEM and pull the wires out of the plug it's going to be more of a PITA but should be able to be done. I think on my second set of plugs I was a little more careless because I had done them without issues in the past.

As mentioned above, I think if you take your time getting them off and use some needle nose and maybe a flat screw drive at the same time to pry them up you'll have a greater chance of everything working out just fine.

Also like mentioned above, if you have someone do it I would double check the clips when you pick it up. Just because a paid mechanic does the work does not mean they won't accidentally pull a wire. One of the three clips on my GS300 did not really click into place which ultimately caused misfire issues. Thing is that it took about 1,000 miles after I picked it up before it reared it's ugly head which is why I ended up just replacing all three clips on my GS.

I do suggest getting the magnetized spark plug socket like mentioned in the DIY threads. Makes like much easier and with all the money you'll save DIY it will be worth the extra $17.

I'm not sure the problem here... I've done the plugs on a couple 430s over the years and don't remember having to disconnect the coil packs from the connecting terminal. I seem to remember plenty of room to just pull it out. The rubber stem into the tube bends so easy to pull out without putting strain on the wires...At least, that's what has worked for me. Good luck.

I have not done the LS430 but I did my other car. And that had a lot of stuff to be taken out of the way (inline 6), whereas this one does not. If I am unsure of a job, I always park my car somewhere that it is not in the way, so if anything happens, I can always drive another car and run to the store if need be.

Would you feel comfortable changing a spark plug on a snow blower or lawn mower? If so, I would say go ahead and attempt the car. If not, then I would say no, have an indie do it. What's the worst thing that could happen, strip the plug into the cylinder head, or break a coil pack--while these are not likely to happen, even if they did, not the end of the world if the car is not in the way....my .02

p.s. the lesson I have gleaned from my other forum is to always torque and never use anti seize, and you need a torque wrench that is say 5-75 if you need to do 17 or whatever it happens to be. On the other hand many many people insist they do it by feel--if so, do not overtighten...I did the brakes on my wife's car by feel, and the bolts needed 129 and 48 ft lbs...no biggie

I have changed mine twice,change mine every 50k miles and i disconnect from the coil packs both times.I use a very small common screwdriver and push on the clip with my finger and lift the coil pack connector at the bottom with the driver in a twisting motion. I put a little dielectric grease on the seal on the connecting terminal.

I bought plugs on ebay for $48, independent charged $90 to install.

Did they show any wear after 120k? Any noticeable improvement in engine performance or fuel economy?

No abnormal wear and no noticeable improvement in performance or economy. Only piece of mind that they were done at the recommended interval.

I didn't give it a try without removing the clips. If you can do it without removing the clips then it should be a super piece of cake to change them. I would definitely give it a try without removing the clips.

My BMW needs plugs every 45k and they list for $20 each (what a joke). So rather than go the genuine OE route, I just get the green Bosch OEM instead for about $12. The LS is even cheaper.

Absolutely zero difference when replaced, as in no difference. But again, we don't know more than the engineers so whatever lol

I replaced my spark plugs at 105k miles. It was a pretty easy job. Doing one plug at a time, and having a couple of different size socket extensions, a universal joint, and the Gearwrench magnetic plug socket made it a pretty easy and straightforward job (other than some awkward and tight access which is to be expected in modern cars).

I took my time (maybe 2 hours total at most) and had zero issues with disconnecting connectors on coil packs (used mall screwdriver to unfasten plastic clip on retainers). On some of the more accessible coil packs it is not necessary to disconnect the wire connector.

Denso OEM plugs were $52 delivered on Amazon - had to send first set back as it was fake. Watch out for fake/counterfeit Denso or NGK plugs if the price is cheap. There are lots of fake iridium plugs out there.

I did my GX460 (https://www.clublexus.com/forums/gx-...ug-change.html ) and it was a pain in the butt due to how much stuff was in the way or needed to be removed. I still need to do my LS, though it won't be until the fall when the garage is cooler.