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Is it normal for spark plug cables to shock you when engine is running?? (please read explanation inside)

I've never really noticed this on other vehicles, so I'm not entirely sure if this is normal or not, BUT:

On our '92 Tempo w. 175,000 km on it, I was changing the spark plugs and then fired up the car to make sure it ran ok. Then, before closing the hood I wanted to double-check if the cables were seated properly. So while the engine was still running, I barely touched the cable for the one plug, and was eletrco-shocked. Didn't feel like trying the others...

I don't normally do anything that has to do deal with the spark plugs, so haven't noticed this behaviour on other vehicles. But isn't the whole point in the insulation on the cables to prevent the current from escaping?

I'm pretty sure that the cables are the original stock cables, especially since the previous owner don't seem to have really maintained the car in any way. They're in very good condition though, with no visible wear on them. The distributor don't have any visible cracks, but I haven't yet gotten to check the inside condition of it. Have no idea what condition the coil is in, because it's buried so deep in the engine room that I can't get to it.

Anyhows, I don't need anyone pointing out how stupid it is to touch high-voltage curcuitry while it's live. I just want to know if it's normal for the cables to deliver current through the insulation or if I need to look for faulty components.

Reply to
Mr. Bunny
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No, not normal.

Replace the plug wires.

Reply to
aarcuda69062

Yes it IS normal.. for a car with that many miles on it. Especially if they were the originals which you should be able to tell by looking for cylinder # markings on them.

This is the PRIMARY symptom of old wires that need replaced.... it's one cause of difficult starting when there's condensation under the hood. Insulation degrades over time.. there are pinholes so small you cant see them

Ditto... but dont look for bargains, half the time you might be disappointed or misled into thinking there's something else wrong.

Reply to
Backyard Mechanic

Read his last sentence again.

Reply to
aarcuda69062

Read my WHOLE sentence again

I cant imagine a set of wires that old NOT delivering a jolt when you grab them... or even if they are half that old.

Reply to
Backyard Mechanic

You weren't the original poster.

That wasn't his question.

Leaking plug wires is not normal.

Old leaking plug wires are not unusual.

Reply to
aarcuda69062

{snipped}

Yeah, they definitely have cylinder numbers on them. The rubber is still very flexible, but I can't tell if they have ever been replaced. If they have been replaced with original Ford ones, wouldn't they still look stock?

The one thing about the numbers on the wires that confuses me, is that they say 8 in the distributor end.

I wouldn't even have thought of checking the ignition system, if it hadn't been because the car severely lacked power last we had to take it on the highway. Was so bad that it was jerky when accelerating over 100 km/h, and it was impossible to get it up hills at that speed without it slowing down significantly, and giving some big jumps while fighting up the hill - and that's while have the gas pedal floored.

That led me to try and replace the parts that Mr. Lube have been telling us to replace for the past 3-4 oil changes. Sofar I've only gotten to the air filter and the sparkplugs. I'm a little weary about changing the fuel filter myself, but on the other hand I'm not to keen on paying a mechanic $50 to replace a $15 part, and then not be able to tell if they actually replaced it. Good thing about the fuel filter in this car is that it's strapped to the wheelwell inside the engine room, so it's easily accessible (as opposed to being in the fuel line underneath the vehicle which seems to be common now). Bad thing is that the hose clamps are plastic...

Still have to change the drive belt as well, which is not gonna be an easy task either, thanks to Ford's "brilliant" design job on this car.

I'm not a big fan of Ford, but we got this car for free. Unfortunately it's costed us over $1000 in repairs and parts in the last year and a half. And there's still a long way to go before all problems are solved.

BTW: I ramble, I apologize.

Reply to
Mr. Bunny

No. Replacement plug wires didn't have cylinder numbers on them.

Jerking = an ignition miss.

Plastic doesn't rust.

Reply to
aarcuda69062

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