Ongoing no fire to leading side on Sa model
 

I just bought a 1980 rx-7 ls it took m e a while to get it running but when it finally started it back fires over and over out of the carb and if i let of the gas it dies the ignition coils, spark plug wires, spark plugs,distributor cap and rotor button have all been replaced...so i assume its the timing but i dont know how to check it or adjust it...so if someone could explain that to me that would be great!....also i was wondering if anyone couldl tell me the order of the sparkplug wires i think the person before me got them out of place so a picture or diagram of that would also be appreciated...my car runs very very weak wont drive up any hills and when i try to give it more gas the backfire gets worse..any idea would be great THX!

Could of been found by doing a search. :-)

https://www.rx7club.com/1st-generation-specific-1979-1985-18/distributor-spark-plug-wire-order-402288/

Recommend if you are going to be working on your car then download a copy of the FSM or get a haynes or chilton repair manual.

yeah i use to hav e a manual but ive moved three times since then so i ordered another one but i don't feel like waiting..and i did search or well...tried but this computer sucks and froze every time i tired

1980 Ignition coil information needed
 

I have a 1980 rx7 ls, the leading ignition coil closest to the firewall has no power going to it. I hooked a voltmeter to the contact while the car was running and it showed zero volts. I was curious if this is a bad coil or bad wiring. How hard is it to rewire the coil if this is bad wiring, what would be the best way to rewire the coil if the wiring is bad? Or perhaps a way to test the coil if it works... All help appreciated. Thx

That should be the trailing coil (one closest to the front of the car). When you measure voltage, are you measuring between the coil + and the chassis or are you measuring between the coil + and coil -?

BTW: The '80 only fires trailing sometimes. This is to keep a rich mixture to keep the fire lit in the thermal reactor (emissions control). If you are measuring between coil + and coil -, you will get no voltage (both termianls are at battery volatge) as the coil will not be firing. If you are measuring between each coil terminal and ground of the car, then we will have to explore other options.

Kent

Edit: I see you are talking the about the one closest to the firewall. My bad. Let me know how you are measuring voltage (from where to where) and we'll figure it out from there.

ignition coil wiring
 

MY 1980 RX-7, has no power going to the leading ignition coil...when i take the plug wire off the coil while the engine is running it makes no effect on the engine...SO! i was wondering if you can run the two coils together...like run the positive wire from the leading coil and wire it to the positive on the trailing and the same with the negative...will this decrease the power of the coils? or is there a alternate way to re run the wires for the coil...? THX! Daniel,

Nope. You can do that with the + (it is that way stock), but not with the negative. Otherwise you will be sparking the leading and trailing coils at the same time.

I'm looking at the wiring diagram right now and seeing what the prob may be. I'll pm you in a bit and let you know what I find.

1980 Ignition Coil
 

Can someone post a picture of their leading and trailing ignition coils (1980 only) with the wires included. The coils were replaced on my car before I bought it, and I think they were put in wrong. Thx.

Besides waiting on someone to supply you with a picture. Download a copy of the FSM.

I already gave him a link and he has looked at it I suppose.

Sorry I can't help with the pics. I used to own a '80, but that was like 12 years ago. Also, you should keep everything in one thread. It makes it easier for people to see what you have tried/tested already. It also helps for people searching in the future so they can see the solution to the problem.

Best of luck.

Kent

Please don't start anymore threads on this subject. If you have more questions or such just bump it up with the new info desired. :-)

Sorry bout starting new threads, I'm just kinda frustrated. But yeah you guys are right, I'll be sure to keep everything in this one thread. Ok, a few quick questions...How much would a new leading ignition coil cost me? I'm thinking like 40 bucks or something, shouldn't be too bad. Does anyone know if the coils on a GS are the same as my LS? Thx so much!

Yeah. The coils are the same. You can even get one off an 81-85 if you want. Let'sfirst see if that is the prob, though. It isn't too common for the coil to fail. First, can you verify the voltage reading to coil + and coil - for both coils? Then measure the resistance between coil + and coil -. Between these two, we can see if you are getting power to the coil and if the coil itself is bad. Based on those findings, we can check out the ignitor or the wiring.

Let's just go step-by-step and we'll track down the problem.

Kent

80 ls ignition coils
 

Well this is my 4th bulletin i bought new MSD coils because i thought one was bad...well i was wrong they are fine sooooooooooo.....somewhere my wiring is bad it still shows o volts on the leading coil...the trailing works i found that part out (shocked the hell out of me) but the leading has 0 power...i am starting to wonder if the ground is bad....the ground wires go to some kind of fuse box but all the wires look fine i wired the power wire to the other coil to see if that would work and still no power....is there a list of tests i can try or perhaps someone can tell me how to re-wire it? Or maybe a fuse somewhere?..Is there anyone near morganton NC who has the knowledge and time to maybe stop by and help me with this?

Let's go back to the testing. You never told we exactly how you were measuring voltage (from coil (-) to coil (+) or from chassis ground to coil coil terminal). It makes a difference as the coil (-) isn't ground. It is floating (means coil (+) and coil (-) will be the same voltage if the coil is not charging or firing). If you are measuring between coil (+) and coil (-), then you probably have a bad leading ignitor (in that box you speak of). Other possibility is wiring, but that isn't as likely.

Let me know how you are tking the measurement and we'll go from there.

Kent

well you see i left my volt meter in the back of my car...which has nop back glass and sooooo it rained.....so now i cant measure it but i can stick my finger on the plug turn the engine over and nothing happens...the power wires seem to be wired fine the only one that seemed iffy i straight wired to the trailing coil but still no power so it has to be the negative i think....but i dunno i was measuring from coil point to coil point + and - when this voltmeter worked the trailing showed 13 volts and leading showed 0

So, you were measuring between coil + and coil - (one end on the meter on coil -, the other on coil +)? Is so, the ignitor is probably dead. If your meter worked, it would be could to put the meter - on the chassis (or battery -) and then the other end of the meter on coil + (take measurement) and then coil - (take another measurement).

See, when you measure directly between coil - and coil +, you are just measuring the voltage difference (they could both be at 0v and your meter would read 0 or they could both be at 13v and the meter would still read 0).

If your meter is shot, you could get/make a test light and run the test. This would at least tell you if you had power to the coil. If power is present on both sides of the coil, then the ignitor is likely bad (or bad wiring from distributor to ignitor box, or bad pickup on the distributor).

So, you can either keep testing on you could just throw on a differnt ignitor to see if it is the problem. You would need one from a 1980 (the other years are different). They are called J-105 for what you need. If the ignitor is dead and you can't find another, look up the GM HEI mod on here. This replaces your ignitors with ones that are easy to find (and cheap).

I'll help as much as I can. If you were closer, I would come over and take a look at it for you.

Swap the ignitors out and see if the leading fires. That's the simplest test you can do.

What gauge cable are you using?

ok i will try some more tests and re-post probably tommorow

I checked voltage from both ignition coils from coil point (+) to chassis ground both coils registered 13 volts. So, I reversed the igniters and still only have power from trailing. I swished the igniters back into their original positions then reversed the wiring to the igniters and still...only power from trailing. So, I checked with a voltmeter the contacts leading to the igniters, the trailing side showed .63 volts and the leading showed .02 volts. I assume this means there is something wrong with the distributor. Any other ideas?

From the main harness, 12V wire splits up to the 2 coils (+) and the 2 igniters (+) terminal. hint hint

I take it you were the one who bought that SA in Salisbury that was on Ebay? Anywho. Morganton isn't that far from me. Here's the deal. If you have power going to the coil and the ignitors, but no ground signal coming from the dizzy, than it must be the dizzy. I don't have any more 80 dizzys, but you can always upgrade to a 81-85 dizzy. If your ignitors are good, than you can still use them with the newer dizzy. Seems to be something in the air here lately with dizzys. If your leading pickup has went out, than that will be the 3rd I have seen locally in the last couple months. Wierd?

ok well my compy went down for a few days and its been raining so i havent had much time to to tests...however i did take the dizzy cap off the rotor button and that little bronze shield...thingy.....i saw two sets of red and green wires the side closest to the front of the car was secure but the side to the firewall was loose when i pulled them out the wires had a needle in each one as if to make a connection through a sewing needle...(would that even work????) What other problems could there be?? if my dizzy ground is bad could i rewire it somehow??

OH btw yes i did buy the SA in salisbury off of ebay ^_^ it was a steal and a half...i can drive it with only the trailing coil working and it starts up with no trouble after it warms up but the cold weather is kicking her ass...(it floods out before i can get enough spark to get her started)

Hmm. Seems strange. I never opened my '80 dizzy when I had my SA, but pretty sure the pickups are the same as later models. I imagine that the loose one is the pickup for your leading. See if you can track down a used '80 dizzy to throw in there. That seems like your problem.