Should I wait until there's a problem to change my spark plugs or do preventative maintenance? It's a massive pain.
Posted by funkmon@reddit | askcarguys | View on Reddit | 32 comments
To replace spark plugs I have to remove upper intake manifold and disconnect a bunch of crap. Considering I'll be opening up the engine to outside stuff, changing gaskets, removing throttle bodies, disconnecting hoses and shit, should I just wait until the car has a problem to do this or do it at 100k like Ford says? In my Fusion, sure. I'll replace spark plugs all day, but considering on the Edge I have to do a bunch of dumb shit, some of which opens up the engine, should I take the approach of if it ain't broke don't fix it, or still do preventative maintenance?
I can replace the front 3 easily.
2014 Ford Edge 3.5 liter
Blu_yello_husky@reddit
Most people in this sub will call me a moron, but I don't do preventive maintenance. I don't replace things until problems start happening because of it. They say plugs are good until 100k. But how long do you think you could get them to last until you get a misfire?
Air filter? No lean code, no problem.
Tires? Are they showing chords? No? Run em until there's nothing left.
Transmission fluid/filter? Have you noticed any changes with your shifting? Most transmissions don't even have drain plugs. That means they don't ever intend on anyone touching it in the lifetime of the car. Don't touch it unless you have a real reason.
Oil changes are really the only thing that matters, because if you skip out on that, the first and last sign that there's a problem will be your engine locking up and totalling the car. No other maintenance item has this consequence if neglected
ReactionCompetitive6@reddit
I agree that people waaaaaay over maintain their cars. They seem to do it with pride. Changing their oil every 3k, transmission every 30k, spark plugs at 60-70k, changing belts at 70-90k. After 10 years in their car they’ve spent 3000 on maintance to prevent things that might not ever go wrong and if the do would cost less than the 3k they spent. Of course you always get the guy who says something cataclysmic will happen and you will need an entire engine rebuild at 9k. But like you said. As long as you’re using full synthetic at 5-7500 miles you’re all good.
BossCat77@reddit
I’ve got 285000 miles on my car and I’ve never changed the plugs
AbilerN@reddit
The Edge 3.5L needs a lot of stuff to come out, but it’s easier then it looks. I just did the plugs on my 2013 and it took about two hours doing it for the first time, including the air filter and pcv along the way.
There’s no room to do anything, but I’d rather just do it and be done.
Hipster-Deuxbag@reddit
If you don't mind me asking, what else did you do or replace during the maintenance? Just the plugs, pcv, and air filter?
AbilerN@reddit
No problem, dude!
I did those 3 things, plus brakes all around and an oil change as it needed it when I got it. 106k on it now.
The regular 100k maintenance interval also had me inspect the drive belt (which has no cracks or tears) and requires a coolant change (which I will put off for another month or so until it isn’t below freezing out).
My vehicle is also gets used 3-5 days a week for Deliveries on top of regular use. Under Excessive Idling, or Low-speed Driving for Long Distances as in Heavy Commercial Use it recommends plugs at every 60k and transmission flushes every 30k. So I also will do in a month or so when its warm enough to.
funkmon@reddit (OP)
Well that's not that bad then. Maybe I'll do it too.
I do have a mild concern that I may replace a good plug with a bad one, if you know what I mean. I used to have a G6 and when the mechanic replaced the sparkplugs with OEM plugs even, one shit out after about a year. Luckily it was easy to get to and I replaced it with a $5 one from Autozone, but that maybe traumatized me. I just don't want to do this TWICE.
Slight-Following-728@reddit
I would not wait until there is a problem. Would you rather be stranded somewhere, or do the work ahead of time and know its good?
funkmon@reddit (OP)
I don't mind being stranded.
Slight-Following-728@reddit
That's the dumbest thing anyone has ever said.
funkmon@reddit (OP)
It is what it is. I have 2 cars and AAA. I like the satisfaction of knowing I didn't shell out money for something that wasn't broken, so when I shell out money for something that stranded me, it feels better.
Slight-Following-728@reddit
And what if you get stranded on your way to something important?
Doing preventative maintenance is not "shelling out money on something not broken" its keeping it from braking in the first place?
Why would you even come to this sub to post the question if you're not going to take the advice of people that actually know what they're talking about?
funkmon@reddit (OP)
Nothing I do is important.
I have taken advice from people here and listened to rationale. It seems like the people who are suggesting I do it now are suggesting it primarily for an inconvenience factor. The people who are very specific seem to suggest it can wait a while until it seems like a good project, either due to the engine running poorly or just when I have all the stuff and a day to fix some shit. It does seem to indicate to me that the people with more detailed knowledge say it isn't that important to hit it immediately. Hence, I called a couple mechanics who both suggested to not bother until the engine was doing something weird.
In other words, I asked a question, I listened to what everyone had to say, and when pressed, the guys say the damage that could be done is a fouled cat, which I don't care about since I don't need to pass emissions and would simply sawzall off and replace with a test pipe, and plugs seized. Seized plugs could be bad if I break them off, so that is incentive enough, but not incentive enough to massively prioritize it.
Why do you bother to answer questions when other people have agency and can make decisions? It must be frustrating for you.
TraizenHD@reddit
In that case you've already answered your own question OP, don't bother doing them then.
drive-through@reddit
Definitely do it by 100K, it gets to be harder on the coil packs after that point. I haven’t done them on the cyclone but I’ve done them a few times on the duratec 30 and removing the intake really isn’t difficult at all. Just don’t forget to replace the plenum gaskets. If you’re not comfortable DIYing it, just call a few quality shops and get some pricing since it might not be as bad as you’d think. Definitely ask for the OEM plugs though since, unless it’s a dealership, they’ll install whatever plugs the parts house sends, lowering your future replacement interval significantly if they don’t end up being the right ones
funkmon@reddit (OP)
I got quoted about 500 bucks or 275 for labor, so it's pretty obnoxious. Then, they won't guarantee the OEM parts unless they buy from their supplier who wants 20 bucks a plug.
redditor-tears@reddit
If all you have to do is pull the manifold and harnesses I would just do it. That sounds completely typical in my experience
robbobster@reddit
Deferring maintenance leads to expensive repairs.
funkmon@reddit (OP)
What expensive repairs could this lead to?
PublicPea2194@reddit
leave the plugs in too long you might find them seized into the heads. have fun with that.
I have vehicles that recommend a mileage and a time schedule for maintenance on plugs. 100k miles or 8 yrs. maintenance might just be removing and reinstalling the same set of plugs.
I would absolutely follow the maintenance schedule in regards to plugs
robbobster@reddit
Misfire
midnightcaw@reddit
125k or P0301 to P0306, whichever you prefer. I choose P0301 to P0306 for any engine that requires BS to swap plugs.
funkmon@reddit (OP)
I called two mechanics who quoted me 275 for labor and 300 for labor who also advised to just wait for the check engine light or notably rough running.
I have ordered the parts and I'm putting them in a box in the car just in case.
Sparky_Zell@reddit
I'm not familiar with that vehicle. But is there any type of alternative access to get to your spark plugs?
Only reason I ask is that my van is similar, access is terrible. But I found it ended up being a lot easier if I removed the front wheels, the wheel well liner, and used a combination of extensions and Ujoint adapters. It let me do the job in about half the time then doing it by the book.
funkmon@reddit (OP)
Nope. It covers it. The back right to the firewall underneath the manifold. I don't have to remove the throttle body technically though.
Sparky_Zell@reddit
Again I don't know your engine or layout. But one thing that may help as well is getting an inexpensive borsckpe/endoscope/inspection camera. You can get them for like $25 on Amazon. Or like $50 at home Depot for a Klein one. And then loosely zip tie it to the extension. So that you can always see the socket, but it can also spin independently of the camera. I got one for work as an electrician. But it has helped me out a ton while working on my vehicles. And you could also stick the camera into the hole to see how the inside of your engine is looking while you are there too.
Crawlerado@reddit
There’s an old saying
“If you don’t schedule maintenance, the machine will do it for you.”
funkmon@reddit (OP)
I don't really mind that. It's why I have two.
avolt88@reddit
If you've got a 100k mile interval, those will be either double platinum, or iridium plugs. Plan on swapping them within say the next 15-20k, but make a maintenance day out of it with PCV, filters, and perhaps coolant service as well while you're in there.
You're fine extending them, but if it gets increasingly hard to start or runs rougher, that's your sign to stop putting it off anymore.
funkmon@reddit (OP)
I'm going to do the coolant tomorrow morning since it's pretty much completely separate and I'm flushing the coolant in my Fusion anyway.
I've got all the stuff in my cart online, though incidentally the spark plugs are single platinum, SP-520s.
I've also never replaced the PCV, though it also needs to have the manifold removed, and I have the OEM part in my cart as well.
So do you think it's probably better to wait until I have to take off the manifold to do it and then when I do, whether it's the PCV or a plug or coil, just do it all?
Does it actually cause harm to wait for one of those to go bad before fixing it or am I basically just doing it because it's better to have it be scheduled than not?
avolt88@reddit
Those plugs aren't going to just up & fail on you, though they are well over the projected lifespan for single platinum plugs (60-70k). If you want to extend the next service, iridiums can be installed in place.
Order your PCV & any other maintenance items you need to get and just set aside an afternoon in a week or two to do everything. You'll be fine waiting a couple weeks.
1w2e3e@reddit
Might as well bite the bullet and do it. Better now before it becomes a problem.