I thought I fixed the problem I had a couple months back....fuel wasnt being burnt and only half the ignition was actually firing. Fixed it with a cap and rotor.....

NOW one of my coils is shot again....this is my 3rd set on the car in 3 years. No signal from the coil to the cap....just one coil is working.

My question is, is there anything that can cause a coil to go bad so often? Something in the wiring?

Plugs, cap, rotor, battery cables, battery, starter, grounds, wires (plugs and coils) and coils are all new.

O and my igniters are wonderful....tested them with the test lamp and everything earlier.

 

It's an 85 gs....relatively stock.

 

this seems a bit odd. is it the same coil going dead ALL the time?
i'd tend to think there's a wiring issue. coils can obviously go bad, i've seen it happen, but i've never heard of one car going through multiple coils in such a short time.

 

I wasnt smart enough to keep track. However, the wiring is the only thing I can think of....but who knows.

Could the distributor be doing it? Does the coil get the signal from the distributor to go ahead and fire...or does the coil get the signal first, then send it to the dizzy? ( I would think the ladder...)

 

you said you checked the igniters themsleves, but did you check the wires that plug into the igniters yet? i'm not real smart when it comes to ignitions, but if you don't get many answers, you could try PM-ing Jeff20B. he's great with ignitions.

 

No I didnt, but at least they look good at a glance. They are connected well, but again, I guess it's hard to tell if they are functioning well.

 

I've had the signal wire going to an aftermarket tach ground out and fry a coil before. Which coil is failing and is it always the same one?

 

Like i said, i wasnt smart enough to keep track which one. Sometimes it was both coils...i believe. Again didnt keep track

 

start checking voltage to the coils......low or high is hard on coils. also the big question are you replacing with factory recomended coils or something from the auto parts store that is for a piston engine? The rotary fire three time more often than the piston engine and a sub standard coil WILL fail on a rotary......been there done that...........food for thought. I am upgrading to high fire coils right now, they can take the abuse a rotary can dish out and more go to the fsm and check voltages first, secondaly make sure the chassis ground is good, stray voltage will eat electrical parts. me po on my car ran an additional ground from the battery to the chassis by the coils to make sure the body had a good ground....no problems yet with the swap. pm me if you want to chat we can talk on the phone


joe

 

Most coils fail from not totally releasing their power charge . if you have power at the coil and no fire at the plugs their must be a problem at the cap and rotor assembly .. Their could be a problem inside your dist and it can't release it's power charge properly. Almost any type of coil that I can think of will heat up and fail if it is required to maintain partial charge .. JMO

 

As stated in one of my posts (i think), there is no charge being sent from the coil through the wire to the cap

 

I recall someone on here having trouble with their coils, and it turned out they had the wrong spark plugs... Just something to check.

 

Plugs are right....ive had to buy them enough haha. Thank u tho

 

Your going to have to break it down and verify each leg of the ignition. Heres
how it works:

1. The dizzy has a magnetic pickup that sends a pulse to the ignitor.

2. The ignitor processes this pulse and triggers the coils to fire.

3. The coils have been sitting getting a charge up and when the ignitor pulses the
negative lead on the coil, it discharges on the other ground path, thru the
dizzy cap.

4. The rotor sweeps by as this is happening and sends the spark to a plug.

As you can see a good ground is a must. I suspect you may have a bad ground to
the engine. Its usually supplied via the starter, but if its not a good connection or
the starter bolts don't make good contact that could be a problem. Good ground to
the chassis (the one on the driver shock tower) is not sufficient as this is not the
path you have for ignition.

If your blowing coils constantly it must be because they are overheating, its really
the only way they fail. Coils overheat because they are holding a charge too long
or as someone said, not releasing it all the way. Ergo, bad ground somewhere.

Also voltages are important too. Measure everything agains the FSM values and make
sure its all in spec.

 

where is this ground located, and how is it supposed to work?

 

The ground of the starter is the main ground that attaches to the driver side shock
tower, this then goes up and attaches to the "-" of the battery. It attaches to one of
the bolts down by the starter. It works by being the ground not only for the starter
but also for the engine. Since the engine and tranny are isolated by rubber mounts
you need a good ground to get good spark. The plugs ground to the block where
they screw in.

 

If you want to get technical electrons flow from - to + "positive charge" flows from + to -

https://docs.google.com/fileview?id=...thkey=CKvm3-gE

That's the diagram for an '85, the first few pages even tell you how to read the diagrams.

 

O ok. When i first read your reply i was misled. That ground is the one i took care of about 2 years ago now. I sanded the contact points and put a new bolt in, cleaned it up nice.

 

Are you using stock coils, or aftermarkets?

If aftermarkets, are you sure you're using coils designed for horizontal mounting?

Some of the most "common" aftermarkets, like the common Accels found in the parts stores, are designed to be mounted vertically only, and will lose their cooling oil and overheat if left in a horizontal position.

 

I agree voltage is very important .. Spikes in power either high or low are hard on coils. That is why there is suppose to be some type of condenser at the end of the power supply, to absorb any high spikes and expel power on low voltage .. Although there are those that think they are useless and remove them but that is what they were put there for ,, Also Divin driver is right I have seen lots of coils mounted improper because it was a convenient place to mount or what ever and for sure it contributes to failure,,,

 

Putting in factory coils next week, hopefully that will help

 

Make sure your ground's are good .. It might not be a bad idea to run a ground to the engine from the coil's . Remember ,the path of least resistance

 

What would you connect the grounds to? Just from each negative terminal of the coils to a bolt on the engine?

 

No never on terminals .. Just from the coil base's to the engine or where ever the main ground from the battery goes you must have a separate bolt or threaded hole that isn't being used .. It's just for a back up just so you know the coils are grounded well .. Someone mentioned the the rubber mounts on engine and trans can screw up the ground .. There are very few components on your little car that don't require a good ground ..

 

Another question I have is where the condenser for the coils is located. I'm going over the wiring diagram, grounds, and connections so I want to know where this component is located

thanks guys