Since I am asking a silly question I decided to go all out and include photographs. Perhaps this will aid someone else at some point.
I am testing my old ignition coils for giggles, but I have a question the Hayne's manual was not able to answer. The Hayne's manual says to remove the spark plug cap from the spark plug, but it does not mention removing the spark plug CAP from the cable.
The primary coil tests normal: approximately 4 ohms.
When I test the secondary coil with the cap on I get readings that are too high; i.e. 13.5 kohms to 14.5 kohms.
With the cap removed I get readings that are in spec; i.e. 9.28 kohms to 9.4 kohms.
"Normal" readings are as follows according to the Hayne's manual:
Primary coil resistance: 4.0 ohms +/- 10% at 20 degrees Celsius
Secondary coil resistance: 9.5K ohms +/- 20% at 20 degrees Celsius
For the newbies:
The photos demonstrate how to test the coils, but keep in mind that they need to be held in place firmly. If you're not making good contact with a cable/wire the readings will fluctuate wildly.
Select the correct scale on the multimeter for each respective cable/wire. If the scale is wrong you'll probably get a 1 or a -1. I use a 20 ohm scale for the primary coil and a 20k scale for the secondary coil.
SO, the question remains: should the spark plug cap be removed? Alternatively, are my spark plug caps bad? Did I twist them on wrong?
I am testing my old ignition coils for giggles, but I have a question the Hayne's manual was not able to answer. The Hayne's manual says to remove the spark plug cap from the spark plug, but it does not mention removing the spark plug CAP from the cable.
The primary coil tests normal: approximately 4 ohms.
When I test the secondary coil with the cap on I get readings that are too high; i.e. 13.5 kohms to 14.5 kohms.
With the cap removed I get readings that are in spec; i.e. 9.28 kohms to 9.4 kohms.
"Normal" readings are as follows according to the Hayne's manual:
Primary coil resistance: 4.0 ohms +/- 10% at 20 degrees Celsius
Secondary coil resistance: 9.5K ohms +/- 20% at 20 degrees Celsius
For the newbies:
The photos demonstrate how to test the coils, but keep in mind that they need to be held in place firmly. If you're not making good contact with a cable/wire the readings will fluctuate wildly.
Select the correct scale on the multimeter for each respective cable/wire. If the scale is wrong you'll probably get a 1 or a -1. I use a 20 ohm scale for the primary coil and a 20k scale for the secondary coil.
SO, the question remains: should the spark plug cap be removed? Alternatively, are my spark plug caps bad? Did I twist them on wrong?