Should coil packs be scheduled for replacement?

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Kestas

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I have experienced ignition coil failure on nearly every car I own. They seem to go south around the 100K mark. My Volvo had the coils replaced at 100K, and now again at 195K. BMW is the only manufacturer I know that recommends ignition coil pack replacement at regular intervals (100K). Should this be a routine we do to prevent problems on the road?
 
I think so. I'll be changing mine at 100K, with OE replacement parts, and a fresh set of spark plugs.
 
Nope... When they generate a code. Even a slight misfire will trigger a check engine light. My dad's 2012 Caravan has coil overs on his Pentastar V6 and they are original at 300K
 
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If doing a tune up on a V6 that requires pulling the intake plenum to get to the rear plugs, might as well do the coils at the same time.
 
Originally Posted by mclasser
If doing a tune up on a V6 that requires pulling the intake plenum to get to the rear plugs, might as well do the coils at the same time.


Same goes for the 3.6L Pentastar, the left bank lies under the plenum. No way am I taking that off to change plugs at the recommended interval and leaving the old coil packs behind.
 
In 970,000 miles driven across five vehicles I service (two V8s and 3 V6s, so 34 coils), I have had three coils fail. Two GM vehicles, three Japanese. Were I to be changing them on some schedule, I would have wasted substantial time and money.

If you are worried about a failure, you can stash a spare. Of the three failures, two were on a Toyota Landcruiser ~150k miles. After the first one, I bought a few spares on ebay for under $10 each. Toss one in a storage bin or trunk and then you'll not worry.
 
Two went out on our Acadia at 80k while on out of state vacation. It was a real inconvenience. At the dealer that did the repair the mechanic told me they tend to go out one after another on those cars so I had the other four replaced when I got home. With my 01 Escape I didn't have one go out until 180 k.
 
Regular preventative coil replacement has long been a fact of life for RX-8 owners. Bad ignition can cause excessive engine wear on any engine; combine that with the RX-8's finicky poorly-burning engine and tendency to melt catalytic converters, and it becomes a recipe for disaster. And on top of that, early coils were known to fail. So, yeah -- barring certain aftermarket coil "upgrades", it's pretty much assumed that you should be changing your coils with the plugs every 20k-30k miles.

No way would I feel it necessary to do the same with a modern piston engine. Especially the kinds of engines that most people on BITOG seem to have. The risks aren't anywhere near that level. The coils aren't as likely to fail, and the engine and cat are much more likely to survive when they do.

That said, you certainly can't hurt anything by changing the coils preventatively. And if your coils are hard to get to, changing them is a great "while you're in there" thing to do when you're changing spark plugs or something.

Iridium spark plugs generally last, what... 100k miles plus? At that point, adding a coil change to every plug change doesn't even make a dent in your per-mile running costs. Most people will only have to do it once if ever in the entire time they own their cars.
 
Originally Posted by StevieC
Nope... When they generate a code. Even a slight misfire will trigger a check engine light. My dad's 2012 Caravan has coil overs on his Pentastar V6 and they are original at 300K


Try that on a Ford modular V8 and enjoy driving for months before it actually throws a code... I've gotten really good at using the torque app to find them when you can feel it but no code is being thrown. Between 2 Modular V8 engines with coil on plug, I've replaced 7 coils. The engines had a combined total of 320,000 miles of driving on them combined.

Regardless, I agree that changing them when they go is a better route... (assuming you can quickly diagnose them, even when a code is not being thrown.
 
Replace them when you have access and access is limited, when they fail, or when you go to pull your spark plugs and find this:

received_10155271934256884.jpeg


received_10155271934421884.jpeg
 
in my opinion, if you as a manufacturer routinely find it impossible to design and specify a coil pack that will last the life of the vehicle (or at least 200K miles) with a less than .1% failure rate then you are a total failure. The executive management needs fired, and the purchasing, engineering and testing departments need evaluated and the non-performing persons need fired. I will not be your customer unless you step up and pay for the repairs.

This is why I have my last BMW.

Rod
 
I'd replace them as they fail, unless you get a couple that go bad around the same time.

My grandparent's 02' Chevy Trailblazer had a coil go bad at around 97k miles and 11 years old. Never had a problem for 5 years and 22k miles until they sold it.
 
Originally Posted by MNgopher
Originally Posted by StevieC
Nope... When they generate a code. Even a slight misfire will trigger a check engine light. My dad's 2012 Caravan has coil overs on his Pentastar V6 and they are original at 300K


Try that on a Ford modular V8 and enjoy driving for months before it actually throws a code... I've gotten really good at using the torque app to find them when you can feel it but no code is being thrown. Between 2 Modular V8 engines with coil on plug, I've replaced 7 coils. The engines had a combined total of 320,000 miles of driving on them combined.

Regardless, I agree that changing them when they go is a better route... (assuming you can quickly diagnose them, even when a code is not being thrown.


There is exceptions but it's rare. Most of the vehicles that had codes that we worked on felt fine but the computer detected the miss. Sure enough the coil or coil over was bad but firing just enough to keep the engine from shaking.
 
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