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No Spark? 1979 GL 4WD.


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im alittle confused, i got no spark, after checking voltages, i have nothing on the + wire that comes from the main harness to the ignition coil, i already checked all the fuses and even ohmed out all of them to make sure and still nothing when i turn the key to "ON".. i forcefully jumped power to the coil and still no spark when i crank on it?

what does the transistor box next to the coil do??? i see theres 5wires going to it, 2 are to some electro magnetic sensor in the distributor, 1 is - to the coil, 1 + to the coil and 1 is ground to the vehicle body, but that shouldn't matter because its not even getting power at all to it..

 

Also i just noticed that it no longer tells me what my fuel level is when the key is on "ON", used to tell me until this morning when it refused to start, it started up just fine last night, it does tell me my fuel level when i forcefully jump power to the coil, but still no spark?

 

thanks..

Edited by Subasaurus
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The box is the ignition module,

It intermittently grounds the coil w/it sees pulses from the pickup coil.

 

There is a ballast resistor between the coil and the module.

If you are jumping power to coil + because the normal power source is dead,the module w/only be fed power thru

the resistor and will not get a full 12 volts.

 

Got any voltage at the module w/or w/o the jumper?

2 pins should have power,key on engine off.

1 of them should have steady power w/engine cranking,the other should pulse.

 

I would make sure the ballast resistor is not open and the ignition switch both receives and sends power.(check for a melted plug)

Also make sure there is no voltage between the body ground and battery -.(key on-bad ground if there is).

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i don't know what you meant by theres a ballast resistor between the coil and module and if its open or not. im not even sure how it looks like? :P

and how would i jump power the correct way so the coil could get the correct voltage to see if the problem is a melted wire or plug and so i could test the module output power to see if its pulsing?

 

perhaps a picture will help? i don't know.

 

 

[ I HAVE DELETED THE PICTURE]

DUE TO THE PREVIOUS OWNER 15 YEARS AGO NOT UNDERSTANDING + AND - DIFFERENCES. DON'T WANT TO SPREAD INCORRECT AND FALSE INFORMATION.

 

 

Where is the other end of those 2 wires coming out of the main harness that go to the ignition coil?

Edited by Subasaurus
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Early electronic ignition cars like yours feed power to the coil in run position thru a resistor.

Power to the module does not go thru the resistor

If you hotwire the coil module power WILL have to go thru the resistor(may not work)

I`m not sure where it is located on your car(usually on the firewall)

It will look someting like thishttp://www.autozone.com/1/products/55586-ballast-resistor-duralast-al795.html

 

After seeing the photo,I do not think that is the problem.

 

My info shows the yellow module wire connected to coil -,not +.

Also shows a black/red on coil +

Resistor has a black/red and a black/white.The black/white side feeds power to the module.Black/red side feeds coil positive.

 

"What`s this" is a noise supression capacitor.

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So i was unable to find this ballast resistor.. because the wiring harness goes through the firewall (from the top of the passenger side in the corner behind the strut tower) and unless its between the dashboard and the inside firewall... i can't find it/don't have one. after looking through my 1600 Subaru book, i found this... is the thing they call a "resistor" the Ballast Resistor??
 because apparently the 4WD does not have one (mine).

 

im starting to think i have 2 issues, either the magnetic sensor inside the distributor went out or the coil pack went out, or its the ignition key switch that went out.. is this possible? i've never had the key switch go out on me before on any of my cars, does it just stop working or sometimes it works and sometimes it doesn't? because so far, does not matter how many times i go foward and back, it never reads any voltage on the other side of the harness that goes on the coilpack.

I guess tomorrow im jumping the ignition key switch, see what that does and see if power comes out of the other side.

 

IMG_1397_zpsfedzmu1w.png

Edited by Subasaurus
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just an update, turns out, ignition key switch is working perfectly, and theres 2 wires comming out from the main harness, 1 wire powers the fuel gauge meter in the dash and the other is suppose to deliver 12 volts for the coil, well instead it delivers sparks of horror. theres a short on that wire, well after running a new wire thats fused and replacing the coil with a new one ($13) finally the vehicle is running again, now the charge light is on.

no problem i just disconnected a battery terminal to see if its the alternator, well sure enough i thought it was, after installing another alternator, sparks came out while trying to connect the main + wire to the alternator. so now that wire has a short.

 

does anybody know if anything splices power on that alternator wire and where the other end of it is? can't find anything in the book about it. i just want to run a new wire and discontinue that one.

 

and your colors are right naru, whoever owned my vehicle before me really screwed things up, yellow is -, and black is +, and the noise suppressor capacitor is suppose to be on the -, not + lol  ridiculous, i have no idea how it was even running before, anyways i also found one of the wires coming out of the key ignition switch is cut, after figuring out individually what each wire does, i fixed that issue.

Edited by Subasaurus
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