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Re: inspecting spark plug wires

Posted: January 3rd, 2010, 5:36 am
by Tunes67
I'll chime in a cheap old trick for spotting faulty plug wires. This trick wont tell you if the wires have the proper resistance.. but.. if you have plug wires arcing to ground causing misfires.. this will show you which one and where it is arcing. Wait till really late at night in a very dark place and open the hood while the engine is running. Wait for your eyes to adjust to the darkness and if there is any arcing it will be visible as tiny white pulses along the plug wires. This can also show a disty cap or coil that is arcing to ground as well. A pitch black garage works best.. just be sure you have it well ventilated when running the engine.

Another trick.. grab an inductive timing light.. clip it onto the plug wire you want to check as close to the spark plug as you can get the clip. While the engine is running.. pull the trigger and watch the strobe effect for several minutes.. (Not recommended if your epileptic) The flashes should be regular and consistent. If you see any "pauses" thats a misfire or the spark went to ground somewhere before it got to the sparkplug.

One last thing. When doing these checks.. make sure you have the gap set on your spark plugs correctly. If the gap is to wide, the spark is more likely to find a shorter path to ground. Current always follows the path of least resistance.

Hope this stuff helps

Tunes67

Rough Idle and Stumbling When Warm

Posted: March 26th, 2011, 3:24 pm
by Daninski
Ok, instead of creating a new post I'll simply ask my question here. I replaced my disty cap and rotor. My motor has 190k on it and the plug wires were replaced at some time with Taylor Spiro Pro 8mm wires. When my engine has been warm for a while I get a miss from idle to around 2k. It got a little worst today so I'm not sure of my next step. I could swap out the disty but that's a bit of work since it's on my MX6 and I'd have to remove stuff. Replacing the plug wires would be easier. My main concern is wasting money. Rockauto could deliver NGK wires to me for about $80 bucks. Suggestions (beside me not being lazy lol)

Re: inspecting spark plug wires

Posted: March 27th, 2011, 6:00 pm
by Daninski
No one?

Re: inspecting spark plug wires

Posted: March 27th, 2011, 6:25 pm
by Ryan
Disty! not so hard to get it off the MX6, just some of the airbox needs to move.

Re: inspecting spark plug wires

Posted: March 27th, 2011, 8:43 pm
by Daninski
That air box is a real pain. I plan on going to Performance Improvements midnite madness sale and buy another MSD blaster coil, wire, ect and do a HEI on it. I also plan to do a CAI to sh*t can that fu*kin air box.
:D