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ea81 is perfect [fixed]


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My car sputtered to a grinding halt tonight at around midnight on the hill up to my house--about 10 miles away. It left me stranded for about an hour, waiting for my dad to come with his truck to tow me home. damn. But fear not, there is good news also; it wasn't that bad to fix. All it took was a quick ransack of the parts car for main spark wire thingy and we were good to go.

 

Now here is where the problem is: what could have caused the main spark wire (i'm not even sure if that is what it's called) to go out in the middle of the road? I would like to prevent it if at all possible from happening again. Is this something that just happens sometimes or could it be a problem somewhere?

 

I'm just glad that the ea81 is so easy to work on. It an excellent first car. I've had her for three years and every time she dies, I get her going again. This is why the ea81 makes a perfect first car. I've learned so much from working on it that it makes it worth all the hassles of it breaking.

 

woo hoo

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  • 2 weeks later...

By main spark wire I assume you mean the one running from the coil to the center of the distributor cap right? While any wire can fail, as was stated the spark can jump a pretty decent gap. So an internal break in the wire, when tested, would show infinite ohms (open), but the car could continue to run with no appearent problems (perhaps a small drop in spark gap voltages...). I personally have never seen a coil wire fail by breaking, but I have had them vibrate out of the coil or cap..... however, I have seen what looks like a failure, that was caused by some type of contaminent on the wire. Remember, that large voltage is looking for ground, and if the resistance across the plug gap is greater than resistance somewhere along the wire (that is, the spark can reach ground prior to the plug), the spark will never reach the plug. An example of this would be cross firing inside the dist cap (this can sometimes be seen as a light carbon trail inside the cap). Any chance you might have had a dirty wire/boot or the like? (come on... be honest, were you out playing in the mud?...hehehe :brow:) Many things can cause a spark not to reach the plug, but it seems llike dirt/oil and water tend to be the main culprits (e.g.; water in the cap....)

But like you said, the ea81's are fairly simple to work on. And being able to diagnose a problem and solve it on your own is a great skill to have. And even if you can't fix it yourself, if you have a good idea of what the problem is, it's a lot harder for a shady mechanic to pull one over on ya.

 

As a slight side note..... while taking auto shop in high school, my instructor liked to remove the coil wire from the test stand engines and replace it with a piece of similarly sized rubber hose. ;) Then have the students trouble shoot why the engine wouldn't run. (they rarely check the coil wire) However, one day after swapping the wire for a hose, the students started the engine right up with no problems. Turns out he had used a piece of dirty hose.....the spark was traveling down the inside of the hose along the water/dirt, delivering the spark right where it needed to be! hehe

 

NV

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By main spark wire I assume you mean the one running from the coil to the center of the distributor cap right? While any wire can fail, as was stated the spark can jump a pretty decent gap. So an internal break in the wire, when tested, would show infinite ohms (open), but the car could continue to run with no appearent problems (perhaps a small drop in spark gap voltages...). I personally have never seen a coil wire fail by breaking, but I have had them vibrate out of the coil or cap..... however, I have seen what looks like a failure, that was caused by some type of contaminent on the wire. Remember, that large voltage is looking for ground, and if the resistance across the plug gap is greater than resistance somewhere along the wire (that is, the spark can reach ground prior to the plug), the spark will never reach the plug. An example of this would be cross firing inside the dist cap (this can sometimes be seen as a light carbon trail inside the cap). Any chance you might have had a dirty wire/boot or the like? (come on... be honest, were you out playing in the mud?...hehehe :brow:) Many things can cause a spark not to reach the plug, but it seems llike dirt/oil and water tend to be the main culprits (e.g.; water in the cap....)

But like you said, the ea81's are fairly simple to work on. And being able to diagnose a problem and solve it on your own is a great skill to have. And even if you can't fix it yourself, if you have a good idea of what the problem is, it's a lot harder for a shady mechanic to pull one over on ya.

 

As a slight side note..... while taking auto shop in high school, my instructor liked to remove the coil wire from the test stand engines and replace it with a piece of similarly sized rubber hose. ;) Then have the students trouble shoot why the engine wouldn't run. (they rarely check the coil wire) However, one day after swapping the wire for a hose, the students started the engine right up with no problems. Turns out he had used a piece of dirty hose.....the spark was traveling down the inside of the hose along the water/dirt, delivering the spark right where it needed to be! hehe

 

NV

 

Oh man, I HAVE to try the hose trick at school. That would be hilarious!

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Hey there!

 

Thanks for your help, but I probably should have edited it to say fixed or something. Turns out the plug wire was just a coincidence and after troubleshooting for about a week and 6 strandings (ouch) it turned out to be the pickup loop in the distributor. Pain in the rump roast to diagnose on the side of the freeway, but I'm glad it is over.

 

Again, thanks for your help!

 

-Kevin

 

By main spark wire I assume you mean the one running from the coil to the center of the distributor cap right? While any wire can fail, as was stated the spark can jump a pretty decent gap. So an internal break in the wire, when tested, would show infinite ohms (open), but the car could continue to run with no appearent problems (perhaps a small drop in spark gap voltages...). I personally have never seen a coil wire fail by breaking, but I have had them vibrate out of the coil or cap..... however, I have seen what looks like a failure, that was caused by some type of contaminent on the wire. Remember, that large voltage is looking for ground, and if the resistance across the plug gap is greater than resistance somewhere along the wire (that is, the spark can reach ground prior to the plug), the spark will never reach the plug. An example of this would be cross firing inside the dist cap (this can sometimes be seen as a light carbon trail inside the cap). Any chance you might have had a dirty wire/boot or the like? (come on... be honest, were you out playing in the mud?...hehehe :brow:) Many things can cause a spark not to reach the plug, but it seems llike dirt/oil and water tend to be the main culprits (e.g.; water in the cap....)

But like you said, the ea81's are fairly simple to work on. And being able to diagnose a problem and solve it on your own is a great skill to have. And even if you can't fix it yourself, if you have a good idea of what the problem is, it's a lot harder for a shady mechanic to pull one over on ya.

 

As a slight side note..... while taking auto shop in high school, my instructor liked to remove the coil wire from the test stand engines and replace it with a piece of similarly sized rubber hose. ;) Then have the students trouble shoot why the engine wouldn't run. (they rarely check the coil wire) However, one day after swapping the wire for a hose, the students started the engine right up with no problems. Turns out he had used a piece of dirty hose.....the spark was traveling down the inside of the hose along the water/dirt, delivering the spark right where it needed to be! hehe

 

NV

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