Coil packs how long do they last?

[blue62]

Originally Posted by Boxstard

I know continuity and resistance are two different things, but effectively you are checking both at the same time when you are checking coils with a multimeter for breakage, short or insulation leakage.

I agree that you can waste time doing all those tests to pin point the coil issue when you can just buy new ones and forget about it, ‘if you have any doubt’…. my point is how to confirm that doubt by reasonable test so that you don’t end up just replacing perfectly good coils with zero appreciable improvement. They are not expensive, it just bothers me wasting good parts, just because I can replace them.

I have never found a coil to be at fault where I could not detect the fault.
I have always been able to see physical damage, high Ohm's resistance, weak yellow spark. Or no spark.
That is over a period of 50+ years of playing with cars.
I have had very few coils fail.
Although in my old VW bug, heat from the engine was hard on them.

[Boxstard]

Originally Posted by blue62

I have never found a coil to be at fault where I could not detect the fault.
I have always been able to see physical damage, high Ohm's resistance, weak yellow spark. Or no spark.
That is over a period of 50+ years of playing with cars.
I have had very few coils fail.
Although in my old VW bug, heat from the engine was hard on them.

My takeaway from this threat is no need to change coils as PM, as they can last long time and you will likely notice symptoms. It is my habit to change spark plugs routinely at much shorter interval as factory suggests, so I can read them to see health of combustion and detect weak spark, if I don’t feel it from driving,

My first car was a 73 VW bug and probably the very first thing I did for ‘performance’ upgrade was Bosch blue coil….. I guess I’m spoiled now, no need to adjust valve gap every 3K miles, adjust distributor point gap, set the timing with strobe light, fiddle with carburetors, etc….