Cap, rotor and spark plug wires

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My Accord has almost 200,000 miles on the original ignition system (sans spark plugs changed once). Cap, rotor & wires are often mentioned as part of a complete tune up. What are some signs they are going bad? My car seems to run fine but should I just replace them anyway since they're most likely past their prime? Or should I just follow "if it ain't broke....?" Would I see benefits such as smoother idle, higher MPGs, etc?
 
Those components are overdue. Mileage, smoother more responsive operation and performance gains. Cap and wires could also give some misfiring issues in damp conditions.Remember it takes more energy to fire the plugs with worn ignition parts and worn, widened gapped plugs.That stresses coils as well.Tune ups are preventive measures that are worth doing when called for. Also, change out the often overlooked gas filter.Performance gains and your fuel pump will thank you.
 
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Hondas had distributor issues in the mid 90s, not sure if yours is past the controversy. If your distributor conks out in six months the new one might come with cap & rotor as well.

If you do replace these parts, go OE, they've done you well.
 
Originally Posted By: Lubener
Those components are overdue. Mileage, smoother more responsive operation and performance gains. Cap and wires could also give some misfiring issues in damp conditions.Remember it takes more energy to fire the plugs with worn ignition parts and worn, widened gapped plugs.That stresses coils as well.Tune ups are preventive measures that are worth doing when called for. Also, change out the often overlooked gas filter.Performance gains and your fuel pump will thank you.



What he says. Plus you've gotten your money's worth out of those parts 2x over.

Also what eljefino says...get top quality parts and not the autozone or Pep boys generic garbage. Brass contacts are found in premium caps and rotors. Don't buy the parts with aluminum contacts.
 
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You have a 2002 with those old style ignition parts? My 2001 Civic had coils on each plug. Never had an issue with anything for 227k.
 
FWIW the GM service manual calls for plug wire replacement at 100K when you replace the plugs. This is to help protect the expensive coils which may go bad if the wires start misfiring.
 
Considering a set of Denso (OEM I'd assume) wires runs $32 and a cap/rotor combo runs $23 I see no reason to not replace with the next plug change. I've had good luck with the Denso Platinum TT plugs as well.
 
Originally Posted By: mclasser
My Accord has almost 200,000 miles on the original ignition system (sans spark plugs changed once). Cap, rotor & wires are often mentioned as part of a complete tune up. What are some signs they are going bad?


As mentioned, running rough or missing in damp conditions, or arcing while running the engine at night. But by the time you see these things, the plug wires have already degraded quite a bit.


Originally Posted By: mclasser

My car seems to run fine but should I just replace them anyway since they're most likely past their prime? Or should I just follow "if it ain't broke....?" Would I see benefits such as smoother idle, higher MPGs, etc?


Yes, no, yes and yes! I've always been pleasantly surprised at how smooth the vehicle idles with new plugs, cap and rotor.
 
Which engine do you have?

Most engines
Originally Posted By: Chris Meutsch
You have a 2002 with those old style ignition parts? My 2001 Civic had coils on each plug. Never had an issue with anything for 227k.


Yes, what MY2002 engine do you have that doesn't use coil-on-plug?

Coil-on-plug modules rarely degrade subtly. I've had the connector boot split, resulting in the same symptoms as bad plug wires. Before the boot split, the engine ran normally. Immediately after, the engine missed under load. It's even more true of the coil. The coil modules typically fail completely, rather than having reduced output.

ODB2 engine typically monitor crank acceleration, and can detect uneven cylinder power. Unless all degrade equally, the ECU will raise an error before you'll detect rough running.
 
Update: I tried inspecting the cap & rotor today. Three 7 mm bolts hold the cap on; was able to get two off but the last one was a little hidden and required feeling around for it. For some reason, it was already loose and just spun in place. I'm the original owner and can't a recall a time the cap or distributor itself was ever removed from the car
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The cold wind eventually picked up so I just lost patience and went inside. The external dist. seal is leaking so I'll try removing the cap then with the dist. off the car.

Originally Posted By: Chris Meutsch
You have a 2002 with those old style ignition parts? My 2001 Civic had coils on each plug.

Yep, the F23A engines have the older style ignition system. Here's a generic pic of the engine from some eBay listing:
04.jpg
 
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