Gyro_Bot

Hi folks, after searching, I could not find a thread about "testing" our ignition coils. The stealership says my leading ignition coil in rotary chamber 1, is arcing and needs to be replaced.

I have two replacement ignition coils, so I was planning on replacing the failing ignition coil and the next "worst" ignition coil in the set.

After looking on this form and then You-Tube, there isn't any videos on how to test our particular brand of spark plugs with a multimeter.

This is what I have:



The plug on it's side is the one that is supposedly arcing. However the multimeter (Ohms) does not give me any readings on these coils.

First question:
1: HOW do I probe our brand of ignition coils to get some numbers to start comparing.

Second question:
2. Just curious if I have the right numbers to look for:
Up to 0-200 Ohms first test = around 1.7 is good right?
Up to 0-20k Ohms second test = around 8k ohms is good right?

Third question:
3. I assume the 1st rotary chamber is the one closes to the front bumper. The second is facing the drivers cabin area?

I'd really like to get my car running again, but I don't want to replace the wrong coils.

Thank you so much gentlemen!

Gyro_Bot

Assembling some info from a relevant pose....

Gyro_Bot

Ignition Coil test thread

Yes! found it!

RIWWP

iTrader: (2)

That test doesn't test our igniter, and the igniter is what fails. Use a spark tester like this http://www.auto-repair-manuals.com/E...4C4aAn3O8P8HAQ

Test each coil at it's plug wire while idling, swapping plug wires if you find a problem to confirm if it's the wire or the coil. You will need the other 3 coils powering their plugs normally during the test, turn off the engine to plug the plug wire off the plug and onto the tester. Clamp the tester to a ground point.

You are looking for a bright clear blueish white spark that is stable in firing rate and color.

RIWWP

iTrader: (2)

The resistance test will pass a coil that can't hold a stable spark

Gyro_Bot

Hi RIWWP,

So your saying... there is no way to know which coil is dead, based on readings from a multimeter? oh great....

The shop said that it was the 1st rotor chamber and it's the idling ignition coil. Which would be the leading coil / spark plug. So.. numbering from front bumper backwards into the car... the rotor chambers are numbered 1 and 2? (2 facing the rear bumper?) so... by that same token.... (out of the set of 4 coils) the number #2 coil, and perhaps it's plug, need replacing?

Here some findings:

I'm having a problem with this. I am getting some strange values from the 4 pulled from the car and one of my brand new ignition coils. I am also using a multimeter, and I think I'm using as described in the test cases above.
Not Used
Black Wire Tester
Red Wire Tester


#1 Ignition Coil Test Results

----20M ------------ 20M ------------- 2K
C:.:B:.:A ------ C:.:B:.:A ------ C:.:B:.:A
---9.58 ----------- 9.59 ------------ 0.961



#2 Ignition Coil Test Results

----20M ------------ 20M ------------- 2K
C:.:B:.:A ------ C:.:B:.:A ------ C:.:B:.:A
---9.50 ----------- 9.50 ------------ 0.9



#3 Ignition Coil Test Results

----20M ------------ 20M ------------- 2K
C:.:B:.:A ------ C:.:B:.:A ------ C:.:B:.:A
---9.46 ----------- 9.46 ------------ 0.90



#4 Ignition Coil Test Results

----20M ------------ 20M ------------- 2K
C:.:B:.:A ------ C:.:B:.:A ------ C:.:B:.:A
---9.68 ----------- 9.7 ------------ 0.912





#NEW Ignition Coil Test Results

----20M ------------ 20M ------------- 2K
C:.:B:.:A ------ C:.:B:.:A ------ C:.:B:.:A
---9.1 ----------- 9.1 ------------ 0.888


Looks like the brand new coils have the lowest values. Also, the shop told me one of my coils was arcing and needed replacement. So... if they all look about the same... does that mean it's more likely the spark plug that is the issue? I have 1 brand new Lead and 1 brand new Trailing spark plug. So if need be, I can update those.

I just want to know if: 1. I'm taking these readings correctly. 2. Are these values normal?

Thanks!

RIWWP

iTrader: (2)

The multimeter test does have relevance, in that it does test the internal circuitry. If a coil fails that test then the coil will not fire at all. And correct, newer coils will have lower resistance numbers than older. However, it doesn't test the igniter, and coils with failing igniters will pass the multimeter ohm test. For the RX-8, what you have to test is the spark, so you need a spark tester.

Use this for which is which

Gyro_Bot

Thanks! yes that actually helped.

I replaced the idle ignition set of coils with the new ones. Then randomly swapped the trailing coils (#2 and #4) until the engine could clear the upper bands without hiccups.

This worked out very well, and I didn't even need to change my plugs. Which are less than 10 months old anyways.