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Spark plug wire resistance too low?


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Mine are all way below the specs listed in the '89 FSM (the online pdf).

 

Wire my-ohms fsm-ohms

coil 0.43k 2.5k-6.5k

1 1.25k 9.5-22k

2 0.5k 3-7k

3 2.1k 9.6k-22k

4 0.43k 2.5-5.5k

(some spec numbers were rounded)

 

Haynes and Chilton aren't helping. I am reading the meter correctly, and it works. Car in sig. Wires are Bosch 7mm, 40k miles I have on them, I dunno before that.

 

Can the resistance be too low? Should I be happy because they are so low?

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I dont personaly see why low resistance can be a problem, i know that the less resistance you have ther more the spark gets to the plug and less energy is lost on its way from the disty, which means better spark, and less heat in the wires, although im might be missing something, thats my 2 cents :)

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From your readings it seems there is approximately a x10 error. By multiplying the readings by ten they would be within spec.. If you are using a analog meter are you on the x10 scale and not alowing for the multiplier? If you are doing it correctly try using the x100 scale and see if that makes a difference. There may be a problem with the x10 scale of the meter.

 

I would worry about the wires being bad unless there is a problem with the engine performance.

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I dont personaly see why low resistance can be a problem, i know that the less resistance you have ther more the spark gets to the plug and less energy is lost on its way from the disty, which means better spark, and less heat in the wires, although im might be missing something, thats my 2 cents :)

That's what I was thinking. I'm also an EE major.

 

Digital multimeter. Works perfect. But for troubleshooting I measured some resistors and used all like 8 scales, and everything checked out.

 

Car ran fine ignition wise, but I've been checking everthing before I put it back together. The engine did overheat very badly before I tore it apart. I could see the extra heat in the wires making it tough for the spark to travel at the time, but I can't think of anyway the wires could get cooked and be bad with LOW resistance. Getting cooked and like losing a solder connection or something is another matter.

 

Score one for Bosch! Good thing cuz I don't have the money for Magnecors now.

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