Changing spark plug wires

plug

#1


What is the recommended interval for cars newer than 1987?



My 1987 Car starts/runs fine - since I bought it, I did 50k.



Is there any benefit in changing it?



Is there any benefit to the engine as well?


#2

If your car is running fine, leave it alone. Replacing spark plug wires at regular intervals is done mostly for preventative maintenance.

One day you will note an occasional engine miss, or your car will have trouble starting up on rainy days. Then you will know you should have changed those wires a week earlier. That day may not come for another 25K miles however.

Spark plugs are another matter. You can inspect them, and you should be doing that at about tis time.


#3

A realistic interval is every 50,000 to 75,000 miles to change the spark plugs and wires, both. The damage can be done to the catalytic converter before you’ll ever begin to feel the misfires.


#4

You mention about damage to the Catalytic converter!

Is this due to Spark cables?

My plugs are changed regularly. But not the Spark cables.


#5

well, i have had good luck with 100,000 mile wire change intervals or go with the timing belt ones, ie: if belt is every 30,000 go with a 90,000 mile change, if belt 100,000 go with that etc. I do highly recommend to go with the OEM wires, most over the counter after market wires are not as good as OEM and not the perfect match for lengths for all plugs etc, OEM will make the replacement a lot easier. Good wires are expensive and cheap ones cna make the engine run like crap


#6

It’s hard to follow what you are saying!


#7

Very easy way to tell . Open the hood at night with the engine running … do you see blue sparks around the wires ? If you do you need to replace the plug wires .


#8

The new plug wires will pretty much last the life of the engine. Had one engine with 220k on them, never missed.

If you do replace them, use only OEM grade cables, do not use High Performance cables. The High Performance cable have lower resistance, and the literature on the subject sounds good, but lower resistance causes the coil to discharge too fast and results in a short duration spark with LESS total energy than with OEM grade cables. The OEM cables should have about 4k of resistance.


#9

The new plug wires will pretty much last the life of the engine. Had one engine with 220k on them, never missed.

Agreed 100%. All I do is wipe the wires down with a damp cloth a couple times a year. That’s it. I’ve had wires last well over 200k miles.


#10

A realistic interval is every 50,000 to 75,000 miles to change the spark plugs and wires, both. The damage can be done to the catalytic converter before you’ll ever begin to feel the misfires.

Want to explain that one. What damage to the catalytic convertic??