Coil failing?

[greentee76]

I searched and did not find anything on this so I wanted to ask.
First of all, car started missing a little when cold this weekend, after it warmed up seemed fine. Acted up a little bit yesterday on my way to work so I ordered a set of plugs (NGK V power) and replaced them. Same. Today I got a cap and rotor and replaced them(did not look bad). Found some corrosion on plug wire ends and while cleaning broke off an end. I had a new set of wires so put them on. Same. Misses at idle, either doesn't miss off idle or I can't notice it. So, new plug,wires, cap and rotor and still a miss. I tried adjusting the Weber as some have said they have to do when the weather changes( I have never had to touch it ) to no improvement.
This leads me to speculate that my coil is failing. I remember I buddy got shocked by it when he touched it not that long ago.
Do coils fail slowly or all at once? Do the coils on 3geez have a tendency to fail?

[itzdave]

dont know if i can really answer ur question. but if ya need a new coil i recommend an MSD blaster II coil. easy to install, and makes it run a lot smoother...

[ecogabriel]

If you have a multimeter you may check coil resistance either following the service manual or autozone's free repair info. I believe (can't recall) that the data info regarding coil values in autozone is the most approximate.

I got one coil failing without warning of any kind (5G civic) and when tested its resistance values were off. I do not see any reason why it may not start showing problems without failing completely. Still, I wonder whether a failing coil would show problems when asked to work harder (higher rpms) when it has less time to charge and cycles more often.

You may get a new coil and give it a try; if it is not the problem just return it (I did that...)

[greentee76]

@itzdave-
I will probably upgrade to a higher output coil later on. For the time being I bought a new standard one.

@ecogabriel-
I thought about testing it but the specs are for 70 degrees F. It is currently 30 degrees or so.

Update: replaced coil, no change.
Found that my adapter plates for the weber are leaking. I thought I checked this when I checked for vacuum leaks, but I think maybe I didn't spray around the plates as I didn't want to know that was the problem. Ha.

[G. White]

When my coil went bad, it just gave up the ghost all together....wouldn't start the car at all. Luckily I had a spare lying around, 2 minutes later I was golden like the shower!

[ecogabriel]

Update: replaced coil, no change.
Found that my adapter plates for the weber are leaking. I thought I checked this when I checked for vacuum leaks, but I think maybe I didn't spray around the plates as I didn't want to know that was the problem. Ha.

I found a little strange that a idle problem caused by spark would not be more manifest when engine revs higher (and the coil has to work more).
I have become quite unfamiliar with carburetor problems as none of my clunkers are carbed.
What you mentioned about the adapter plates leaking makes sense; a small leak would impact idle but once the engine accelerates it would not that disturbing. Can it be solved (new gasket, etcetera)?

[greentee76]

I found a little strange that a idle problem caused by spark would not be more manifest when engine revs higher (and the coil has to work more).
I have become quite unfamiliar with carburetor problems as none of my clunkers are carbed.
What you mentioned about the adapter plates leaking makes sense; a small leak would impact idle but once the engine accelerates it would not that disturbing. Can it be solved (new gasket, etcetera)?

Yeah, I just need to order the gaskets and pull it down and reseal. Not really that big of a deal really. I turned the idle up a little and lived with it through the holidays with no ill effects. Actually averaged 32.5 MPG on a trip accross the state.