What's the best way to check spark plug/wires?

Well .. the old grand prix is missing again... I picked up a 'plug wire' tester, but it's about as useful as a tank full of lead .. What is the best way to check the wires, and plugs?

Reply to
clevere
Loading thread data ...

Wires? Ohm Meter. Plugs? Visual.

Reply to
Bon·ne·ville

Here we have the tip of the plug grounded to the car somewhere and turn the car over and watch it. If it sparks it's good.

Reply to
Phillip Schmid

At night, with no lights, start car and look to see if any of the wires glow in the dark. Plugs is a visual thing.

Reply to
jpk

Reply to
clevere

Ohms is part of a multimeter. Did you mean to ask how to check them with=20 it?

This is a copy of one of my older post

----------------------- In general conventional plug wires have a resistance of 10,000 to 15,000 =20 ohms per foot of length. For cables less than 25 inches in length,=20 resistance generally should not exceed 30,000 ohms. For those over 25=20 inches in length, the maximum acceptable reading is 50,000 ohms.=20 Specifications vary with car makes so checking with your service manual=20 is a good idea. If you run platinum plugs you might want good low=20 resistance wires because Platinum plugs in of themselves have a higher=20 resistance than a plain copper plugs. Usually none of my new wires I use=20 go above 5k ohms and I return them if any read over 25k-30k ohms.=20 Returning wires are easier than dishing out money for replacing a=20 damaged coil. When installing new plugs its not a bad idea to use a very "thin!"=20 coating of high temp anti-seize compound near the top of the plugs=20 threads. I say top because people sometimes get a glob of anti-seize on=20 the electrodes and then that plug becomes fouled...

----------------

As for jpk's post i'll add to that. Get a sprits bottle of water and=20 spray a mist over your wires and watch for arching. If they arch they=20 are bad reguardless of resistance. Also grayish looking splotches are=20 good indicators of where wires have been arching.

article , snipped-for-privacy@noway.net says...

Reply to
Bon·ne·ville

clevere wrote : well...the old Grand Prix is missing again.

Where did you lose it this time? LOL !

============================ Check the porcelian for cracks. This happened to two of mine at once about 3 years ago. If your buying new wires buy good ones.

========= Harryface =========

1991 Pontiac Bonneville LE, 3800 V6 _~_~_~_~276,660 miles_~_~_ ~_~_
Reply to
Harry Face

LMAO! It wasn't my fault this time .. Honest. It was the wives. I am going to inspect the plugs/wires tomorrow after work .. hopefully it is something stupid.

Reply to
clevere

Yes. Set it to Ohms, or some meters have a continuity setting.When you touch each lead to either end of a complete circuit, it beeps.

Reply to
Jknomail

Continuity "beep" tester will NOT work on spark plug wires, as the resistance of a GOOD wire is too high

Reply to
clare

Not necessarily so. The wire could be open, and the spark is sufficient to bridge both gaps. In the cyl, under compression, the gap requires much higher voltage, and the spark will "blow out" - making the engine miss. That's why they will often idle smoothly, but miss under load, with a bad wire.

Reply to
clare

My problem is that is idles like crap. It's not a big miss, not enough to cause the engine to sputter, but you can smell gas coming from the exhaust, as well as hear the miss coming out of the exhaust, feel the miss in the steering wheel, and see the engine running rough. But it seems to run fine when revved up a bit.

Reply to
clevere

I see what you mean there, but for one of our cars it was missing at idle and we wanted to see if it was a wire, plug or a DIS thing. So we took the plug and wire out of the cylinder that was missing and put the plug on the ground. Wasn't sparking so we tried a different plug. Still no spark. Tried a different wire (those things aren't fun to get to on a pre-Ecotec 2.2) and still no spark. Then we took off the module and replaced it and voila...sparks :P I think that you could still try that way if it's missing at idle.

Reply to
Phillip Schmid

Thanks! It seems I had myself a bad wire ... grr ..

Reply to
clevere

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.