I have been chasing this misfire at Idle for a long while now.

I have cleaned the IACV, replaced purge valve, did the PCV mod (although my tube is shot and not as tight as I want, getting a replacement).

Today when I was putting everything back together for the PCV mod, and I started it up and was just making sure everything was good, I could hear some loud clicking and clacking. I looked a little closer and I saw some arcing. Only one every 20 seconds or so, but on both sides. Plugs and wires were done about 15k miles ago but no clue on coil packs.

I didn't do the replacement. The wires are the thick blue kind, I might be able to find the shop page for the work oder for the exact part number. Anyway I have a couple of questions.

1. Could the arcing be causing the rough idle?
2. Should I just replace the plugs, wires, and coil packs? Would that help the arcing issue?

 

Yes, that's almost definitely the cause of your miss. I'd pull the plugs to make sure none of the ceramics are cracked. Inspect the plug wires while you're at it.

Was the arching near the plug end or somewhere in the middle of the wire? If it's near the plug end, assuming all the ceramics on your plugs are in good shape, you might get by with a little vaseline or dielectric grease in the end of the plug wire boot.

 

Arcing will definitely cause a misfire. I replaced my plug wires with STI blue plug wires and the starting arcing in less than 5000 miles. They are garbage. I replaced them with Kingsbourne 8MM wires and my arcing and misfire were gone.

 

I it was a bit hard to tell, but it seemed like it was near the plug. I could hear a loud crack but only general flash, I couldn't see the exact spot of the spark. But I could take another look tonight. I obviously need to fix this but I am a little skeptical is the only cause of the misfires since I can only see / hear the arcing every 10-20 seconds and there are a lot of misfires at idle on the Hawkeye.

Happy to have something else to fix though

 

Fantastic, will order these and get them swapped out. Might as well do coils too. Is there a write up / parts list for all the gaskets and stuff I need for the coil job?

Thanks!

 

Get about 4 feet of garden hose; one end to your ear and the other sweeping every spark related crevice at idle You will determine exactly the arcing point, to fix/replace the exact part.

 

Are these the correct wires?

 

That is exactly what I bought. I did the coils and plug wires about a year ago. Had to replace the wires again last month. So far so good with the Kingsbourne.

 

I've run STI wires for 200,000 miles and never had an issue. Not a single one.

 

Start it up in the dark and you can probably see it. Should be a blue arc. I did my plug wires using the "quality" NAPA wires and they arc'd almost immediately. For whatever reason these things are very plug wire sensitive. Not sure if its the routing or the coil power or both. And yes you can change the wires without removing the intake. It's not that bad. I layed down a large piece of memory foam on top of the engine which made it much more tolerable.