The Return Of The Tiggy

Phew.  Turns out the problem with the Tiguan’s engine was not serious — just needed new plugs and coil, so less than $400.  Had the brake fluid replaced and an oil change while it was there, so I picked it up on Saturday morning and it runs like a sewing machine again.

Question:  is it reasonable for spark plugs to last ~100,000 miles?  (They were the premium-priced ones I had installed right after I bought the car back in 2016.)

Of course, they tried to build the ticket by suggesting that my rear brakes were getting thin — but I pointed out that a) the car passed state inspection only three weeks ago, and b) I drive like an old lady anyway, never braking hard unless an emergency looms.

True story:  Some years ago (don’t remember which car it was), the first time I ever braked hard and the ABS kicked in, I thought my brakes had broken so I took off to the dealer quickly.  When I explained the situation the mechanic looked at me like I was from another planet and said:  “You’ve owned this car for over ten years, driven it every day, and you’ve never had to use the ABS?”  I hadn’t.  Didn’t even know what ABS stood for — some kind of magic, I guess.


  1. Im not a mechanical genius by any stretch of the imagination, but I think most modern cars suggest new plugs at 100K. Used to be 60K I think. One nice thing about the computers (I know you’re not a fan), when using top tier fuels and synthetic oils, there seems to be less engine maintenance.

  2. Yes, today’s spark plugs can certainly last 100,000 miles. They use platinum or iridium bits to prevent the electrodes from wearing out, and modern fuel is much cleaner, so they’re less prone to foul. You can wear them out if you, for instance, drive like an idiot, but even then they’ll last longer than they did back in my day.

  3. Glad your vehicle didn’t cost too much to repair. It seems like everything you do to a vehicle these days is 500 to 1000 for basic stuff.

    – spark plugs. Most “imports” (many of which are final assembled in the states) like Honda Toyota vw etc , use iridium plugs. Those plugs are typically rated for 100,000 miles. They end up costing 15 to 20 per plug. Then maybe an hours labor for install. Tack on shop supplies and govt extortion fee, I mean sales tax and it’s usually around 200 to 250. But again that should last 100,000 miles. So. Cheap overall. Iridium plugs last longer and the engines usually run better with them. But anything can break or wear out sooner.

    As far as brakes. Don’t cheap out on those. Get a 2nd opinion if you think a shop is trying to unnecessarily lighten your wallet , but if two shops say your brakes are worn, get them done

    Waiting a few extra miles on dirty fluids isn’t advisable but it won’t end the world.

    Waiting when you need brakes might be the end if you need to stop quick and can’t…

    All vehicles are money pits.

    Happy motoring!

  4. Yes, Toyota’s spark plug change interval is 100k miles.

    I wouldn’t put that much faith and credit in a state inspection, it’s minimal at best in Texas. I would recommend taking off the rear tires and checking the pad thickness personally.

    1. “I would recommend taking off the rear tires and checking the pad thickness personally.”

      Yeah, I’ll get right onto that… after I bake some bread from scratch, build myself a new laptop with a Linux OS, and rebore my 1911 barrel with a Dremel.

      1. With a lot of newer cars you can see the pads through the rims, or with a flexible head inspection camera without taking the wheel off. I also have a floor jack and measuring caliper and could take a look for you. Most pads have noisy wear indicators to determine if it’s time to be replaced. The front brakes do take most of the energy and wear faster, so the rear are less critical. I’ve replaced my fair share of pads, so if nothing else if you just want me to look with my inspection camera to give a quick go/no go determination sometime, just let me know, I’m up in McKinney not far away.

  5. The worst POS I ever owned, even worse than my first car (a Datsun 610) was a 2000 Ford Ranger. It left me stranded so many times I lost track, including the day I drove it off the lot. Once it blew the head gasket in northern MN after a deer hunt with my (field-dressed) deer in the bed.

    But the last straw was in 2010 when the “brake system” light went illuminated on the dash as I was heading to work. I changed lanes and pulled over, testing the brakes as I went; they seemed fine. Went to work, and then dropped it at the local Fix Or Repair Daily dealer to see what was wrong. It was close enough to work to walk over so after work I went to see what was up.

    The guy was telling me that almost all of the components that made up the anti-lock braking system were shot; the sensors and the cabling had been destroyed by the salt they casually dump on the roads there. Bear in mind, the truck was 10 years old and worth (according to KBB) about $4,000. I asked how much it would cost to replace all that, and wasn’t really shocked to hear, “Oh, about $2,000”. I kept asking if the brakes would work WITHOUT the ABS, and was finally told, yeah, they’ll work fine, “…but you won’t have ABS”. I told ’em I’d never kicked in the ABS the entire time I’d owned the truck other than the first winter when I was playing with it on a frozen lake, testing the traction and braking.

    I asked for a small piece of electrical tape and as the tech was watching stuck it on the dash over the little red warning light.

    Then I drove from the Ford dealer over to the Toyota dealer and made a trade for a 2010 Tundra right there. Best thing I ever did with a vehicle.

  6. the plugs in my Toyotas last 100k miles. They can be relatively easy to change. my brother in law has changed a few for me over the past 20 years.


  7. Kim, you’re not the first to take your foot off the brake pedal when
    it starts vibrating / pulsing / shaking what ever you want to call it
    when the ABS is actually working !
    The only time I have ever felt it was intentional, just to see what it
    felt like. Really a strange sensation.
    So far, no one has worked out a cost effective way to reduce of
    eliminate the ‘vibration’.

  8. In a properly running modern engine expensively coated spark plugs can last 100K miles. They seldom do.

    If the coils have been failing the power going to the plug gap has been going down. This leads to degradation of the spark plugs. Since removing the coils is usually the PITA part of the job you might as well replace the plugs while you’re in there and if only one coil & plug is dead you might as well change all the plugs. Unless you’re really cheap.

  9. Modern cars have undersized brakes in the rear, designed to wear out rapidly.

    I was told a story here in NC, that Chrysler and Bendix had a onsite with the NC State Highway Patrol. The first cop chargers were equipped with consumer brake calipers and pads in the rear. The NCSHP was going through a set every 3 to 4 days.

    I guess this is related to efforts to lighten vehicles to get those better CAFE numbers, while attempting to keep the safety factor at the edge.

    Finally, for plugs, never push them past 100K. And personally, it sounds like that was too far for the stock ones in your unit, since you had to replace a coil.

    The ECU will increase spark power on a marginal plug, by charging the coil longer, and this will rapidly destroy the coil. Plugs are generally a lot cheaper than coils, though nowadays with as much crap as you have to remove, who knows?

  10. I have an 2018 Audi Q3 with the 2.0L turbo and the service schedule is 60k miles. I am about 15k miles short of needing that service. That 2.0L has been used at Audi/VW for over 20 years and has been normally aspirated, supercharged and turbocharged. The most popular configuration has been the turbocharged where it has been configured to put out 140 to 330 HP. The spark plug replacement can be as little as 30k miles or up to 100k miles.

  11. My F-150 went wonky on me one morning in April missing a lot so I took it out on a country road and hit the gas hard and made it twice as bad, glad it was still running when I took it in to a good repair shop near us. The shop owner did all the computer stuff on my truck and turns out there were two coils messed up and the plugs were original plugs with 130,000 miles on them since 2008. Got things repaired and gas mileage improved a lot.

  12. You indicate singular coil. Each plug has a coil nowadays, so keep an eye on your little German gem – if one coil failed, the others are likely to do so as well. When I used to do a full service for others, all 4 coils and new plugs were put in. That avoids PO’d customers.

    If cheapskating (my own car) just did the bad one that failed and kept on going. And yes, like many have commented, modern plugs do last 100K even though VW I think had a 60K replace in the owner manual (likely to generate business for the dealer).

    The one thing I am religious about is the DSG transmision fluid and filter every 40 K – cheap insurance. Also diesel filter every 40K (VW says 20K – see dealer profit comment above) and brake fluid and coolant full drain/refill every 3 or 4 years. Again, cheap insurance, especially here where we have very cold weather most of the year and high humidity in summer.

    Lastly – NEVER run your timing belt/water pump/idler past 100K miles. If you drive like an animal (Chicago drivers) maybe even every 85K. Again, 1000 bucks now or 6000 for new engine later.

  13. any shop will tell you when the brakes are getting thin enough that they’ll likely need replacement before the next scheduled service when driven like the average person would drive it.

    Not only does it give them a potential extra bit of income (though that’s simply pulled forward from the replacement date that’s coming anyway) but it prevents them from being sued if the owner goes off and causes an accident because his brakes failed.
    And that second is far more important.

    It’s the same with tyres. They see the tyres will need replacement in 10k miles (given average use), the car needs service in 15k, they’ll tell you that you may want to replace them now. I don’t hold that against the shop, it’s a good thing for them to suggest.

    The reverse is far worse and I’ve experienced it. Had a car with tyres that were barely legal (they had a few hundred miles left on them said the shop), but the lease company refused to have them replaced.
    I told the lease company they were paying for new tyres or I’d refuse to accept the car back from service and they’d have to get me a replacement at their expense for the 6 months that were left on the contract.
    Never seen a beancounter change their tune that quickly. New tyres were on in less than half an hour 🙂

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