Replace coil packs with spark plugs?

Originally Posted by MolaKule
Originally Posted by exranger06
Replace coil packs on an as-needed basis only. If the car is running fine with no misfires, leave them alone. If one coil goes bad, replace just the bad one and leave the rest alone.


I have never had a coil failure on any car with a Coil Over Plug. I replace plugs every 75k miles.

If you have a coil or plug misfire, the ECU should detect it and give you a code when the CEL comes on.

Even my older 1999 S-10 V6's software picks up a plug misfire.


You must have never had a Ford Modular engine. They blow the coils all the time. And in the trucks they won't set a check engine light.
 
Originally Posted by JeffKeryk
Our beloved 2006 TSX with 195K miles recently broke down; it was the #1 coil. It was about 15 miles away and was towed to a great shop not far from home.
FYI this car has been garaged and well cared for...


Could you have limped to the shop on 3 cylinders and avoided the tow?

I had a coil go out on my T5 Volvo and was able to limp home on 4 cylinders, but it wasn't very nice.
 
My feeling is that if one coil goes, the others are likely to fail soon after... on my Volvo I replaced all 5 with Bosch.

I had a Mazda MPV with a Mazda version of the Duratec 3.0, and it required removal of the upper intake manifold to access the rear coils. So when I had a coil go bad (on the hotter rear bank, of course), I bought 3 new ones and put them on the rear coils and put three of the old ones up front where replacement is easy. And I think I had one of the fronts go out eventually, but I had two spares. I think I used Duralast (Autozone) coils and they were fine.
 
Originally Posted by exranger06
Replace coil packs on an as-needed basis only. If the car is running fine with no misfires, leave them alone. If one coil goes bad, replace just the bad one and leave the rest alone.


Unless they're a PITA to get at. If one fails on my 300 or van, and it's the one under the intake manifold, all 3 are getting replaced preemptively. Otherwise, if it ain't broke don't fix it.
 
Originally Posted by brages
Originally Posted by JeffKeryk
Our beloved 2006 TSX with 195K miles recently broke down; it was the #1 coil. It was about 15 miles away and was towed to a great shop not far from home.
FYI this car has been garaged and well cared for...


Could you have limped to the shop on 3 cylinders and avoided the tow?

I had a coil go out on my T5 Volvo and was able to limp home on 4 cylinders, but it wasn't very nice.

Could be hard on the cat, depends on how much fuel is getting dumped into the exhaust.
 
Originally Posted by supton
Originally Posted by brages
Originally Posted by JeffKeryk
Our beloved 2006 TSX with 195K miles recently broke down; it was the #1 coil. It was about 15 miles away and was towed to a great shop not far from home.
FYI this car has been garaged and well cared for...


Could you have limped to the shop on 3 cylinders and avoided the tow?

I had a coil go out on my T5 Volvo and was able to limp home on 4 cylinders, but it wasn't very nice.

Could be hard on the cat, depends on how much fuel is getting dumped into the exhaust.


Had a coil go on my wife's old Rav4 at 390k miles. She limped home about 45 miles. P0420 (bad catalytic converter) CEL appeared about a month after that. Coils cost about $55 each for her old car so swapping them out if it's not necessary is not a good fiscal move unless your think failure is imminent.
 
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Originally Posted by edyvw
Originally Posted by jayjr1105
Originally Posted by edyvw
Originally Posted by jayjr1105
How often do you guys replace your coil packs? Not sure if the manufacturer recommends a certain time for these or "whenever they break"?

What vehicle?

Vehicles are in my sig, Both have had plug replacements on schedule but never replaced coil packs.

I would definiately change cables on Honda since you are doing spark plugs.


His 2005 Odyssey has COP's, no wires.
 
In my opinion, replacing coils only when they fail on a high mileage car, like our TSX, is risky, especially when 1 just failed.
The TSX is driven mainly by my wife for work; she loves that car.
#1 went bad; the car ran very rough as it was down on power 25%.
Limping it home is a bad option; what if it were mechanical and the engine was destroyed?
The car was 15 miles away in Silicon Valley freeway traffic. She called me when it failed.
Sue in in charge of world wide computer operations at a large Valley High Tech.

So replacing the other 3 coils with quality replacements is the smart answer, again, in my opinion.
The little Acura runs like a top again; definitely better than before.
Had I replaced all 4 coils myself at say, 180K, I would be bucks ahead.
An ounce of prevention...
 
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Originally Posted by supton
Originally Posted by brages


I had a coil go out on my T5 Volvo and was able to limp home on 4 cylinders, but it wasn't very nice.

Could be hard on the cat, depends on how much fuel is getting dumped into the exhaust.

You can disconnect the related fuel injector to mitigate that issue.
 
Originally Posted by circuitsmith
Originally Posted by supton
Originally Posted by brages


I had a coil go out on my T5 Volvo and was able to limp home on 4 cylinders, but it wasn't very nice.

Could be hard on the cat, depends on how much fuel is getting dumped into the exhaust.

You can disconnect the related fuel injector to mitigate that issue.


If you just happen to be an excellent road-side diagnostician and happen to be carrying the tools to remove the relevant cover(s) to even access those connectors....lol!
 
I've replaced so many coils on GM 3.6 motors, especially the early 2004-2007 CTS's. I always just replaced the 1 that failed. Almost every time the plugs were past due for replacement so I also do all the plugs. I am a firm believer of changing plugs a little before scheduled to save wear and tear on the coils from working harder and failing. I have done 60k mile spark plug changes on my personal 2008 CTS 3.6DI and I am still on the original coils at 171k miles. I am, to be honest, considering changing them all due to age and miles because at this mileage I sure got my money's worth!
 
I replace them all when one starts to misfire as the others can't be far behind. OEM parts only, no eBay specials.
 
Originally Posted by KGMtech
Coil packs are stressed by the spark gap increasing, along with other factors (oil contamination, oxidization, rough handling). Replace the spark plugs at recommended or earlier intervals to keep the gap to spec and maximize the coil life.


I agree 100%. Your car will continue to run fine with a huge over gapped worn out plug because the coil packs will compensate by working harder to get the appropriate spark. Make sure you change your plugs at recommended intervals or sooner. Or wear out those expensive coils. I would only replace with factory OEM coils as needed. I have never had one go bad so far but I only have Toyotas.
 
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Originally Posted by jayjr1105
How often do you guys replace your coil packs? Not sure if the manufacturer recommends a certain time for these or "whenever they break"?


Only ever replaced 1 coil ( not a coil pack ) in ~ 50 years . Helped Dad diagnose misfires on his & Mom's 1969 Galaxy 500 302 ci . We went down to a local store , he purchased a new coil and it ran fine . Until it eventually was wrecked .

Praise the Lord , never had to replace a coil pack !

So , I would say when / if it goes bad .
 
I had the original coils on my S70 for 20.5 years, and 270k miles. Got a CEL for one of them a few months ago (didn't affect drive-ability) so I replaced all 5 with OE. (Bosch)
 
I replace COP boots with every other spark plug change, i.e. around 240k miles. The boots always have cracks, if you twist and squeeze them a little
 
Originally Posted by pitzel
Originally Posted by circuitsmith


You can disconnect the related fuel injector to mitigate that issue.


If you just happen to be an excellent road-side diagnostician and happen to be carrying the tools to remove the relevant cover(s) to even access those connectors....lol!


DIYers often keep a few tools in the trunk.
Diagnosis consists of disconnecting each injector one at a time until you find the one that doesn't make idle drop.
 
Originally Posted by exranger06
Replace coil packs on an as-needed basis only. If the car is running fine with no misfires, leave them alone. If one coil goes bad, replace just the bad one and leave the rest alone.


100% Concur. And stay OEM. In the old days, aftermarket might have been better but in todays age of coil per plug, OEM's are very good - for the most part...I am sure there are a couple out there that are crappy...lol
 
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