Re: How bad is replacing the plug wires on a 96 z26?
Posted: Thu Sep 06, 2018 10:00 pm
I think the plugs are okay as long as it ran clean and properly the whole time, I wouldn't go past 70k-75k though.Rettax3 wrote:At 65k, the plugs are near or past their lifespan. At 22 years, hey, everything deteriorates with age. Corrosion can effect even the electrodes inside the engine. They are due. As for the wires, if they are original, they are as likely to come off in pieces as in one piece. They are good quality, but if you are doing one, do 'em all, it is worth a little more time.
If you do the plugs, NGKs are great, I've been using the G-Power platinums a lot lately, I used to use the V-Power nickle too. AC Delco (OE) are also a great choice. I've heard a few bad things about Bosch lately, but I still have a few engines with them and they run fine. I don't like Denso, and I don't trust Autolite anymore.
PCV valves don't actually wear out, but they only cost a few dollars, when are you going to replace them? I just do them with the plugs to be sure they are replaced before they plug-up with carbon, at least inspect it while you are under the hood, with that few miles it is likely okay.
I don't recall hearing anyone prefer to do the 3100 plugs from underneath, I'm sure a lot of people do, maybe you could let us know if it is actually easier? Ramps make short work of getting under there, for sure. My '89 GTU with the 3800 SC swap has to be done from underneath (on the rear three at least, the front bank is actually easier to access than the original 2.8 from the top), and it is a PITA to get up in there, even with the manual transmission -the autos restrict the space a lot more too.
It doesn't matter for the fuel filter if the tank is empty or not, so don't let that concern you. You only have to drop the tank to replace the pump or the strainer, the filter is outside the tank, just behind it I believe.
But if you don't know the history of the motor, a plug change is always a good idea.
Still a good idea to pull the plugs and check/clean them every 30k miles depending on their condition, replace early if necessary.
My engine being bought new with all new parts meant I started fresh so my plugs have no build up still, I'm a few thousand miles from my next check but I'm thinking I'll replace mine early just for my trip because I'll be loading a good 40k miles on it in the next several months with the daily driving.
Easier to fix it now at home than out in the middle of nowhere. lol