Remove Spark Plug Wire W/Engine Running?

[Outpost]

In an effort to pinpoint an engine noise, can we use the old hot rodder's trick of removing the spark plug wires (one at a time) until the affected cylinder is found? Will this test damage the distributorless ignition system in our cars?

 

[bruce]

Originally posted by Outpost
In an effort to pinpoint an engine noise, can we use the old hot rodder's trick of removing the spark plug wires (one at a time) until the affected cylinder is found? Will this test damage the distributorless ignition system in our cars?

If you have a weak coil, then disconnecting the wire, can finish it off. Or weak plug wire,

 

[peterkin]

i'm telling you now, that arc doesn't feel to good when it grabs your finger.

 

[channer]

I did mine one wire at a time.... Pull the wire out, threw in a old plug into the wire & started the car. It took a little longer. Didn't find my problem!!!

I later found out that I had a very loose harmonic balancer that probably wasn't tighten to spec!!!

 

[CraigT]

The trick that was used by some TR people is to put about an 1 inch piece of vacuum hose on the coil pack post and then put the plug wires back on. Then turn on the car. Ground out one cylinder at a time with a meter lead.

 

[kh440]

Given what the output of those coil packs are, I would not advise pulling a wire off with it running--ground a test light and use the rubber hose trick--much safer.

 

[equalizer442]

old hot rodder's trick

we have coils the ond hot rodders dont use coils in other words its NOT a good idea on our cars. ive had it arc threw me before and i can vouch for this it will just about put you on your knees.

 

[blackbuick87]

Mine had a bad module with orange spark and just about knocked down my 6'3 old man. Good Luck

 

[Turbo__Tim]

Use clear plastic line like you get at an aquarium supply place. Put it on at the coil pack, and start the engine. (2-3" long)You can safely observe the spark color then. Get the engine compartment good and hot first. Hot coil packs fail.

 

[dpok69]

Im a little confused. We have to put a short piece of hose on one of the coil pack posts and then start the car with one plug wire disconnected?

 

[blackbuick87]

dpock for what its worth I had to use this method yesterday, had a knock on #6, disconnected the plug wire, fryed myself. Ended up using a pink shop rag, it was enough to stop the spark from jumping all over the place

Knock turned out to be the exhaust pushrod had slipped out when I put the rockers on and I missed it since it was way in the back