My LT1 has been running rather annoying lately. I think I might have it tracked down to the ignition system but can't find exactly what it might be. Below is what I have tried.

---wires are new Taylor Spiro Pro OVC
---plugs are new Autolite AP106. Also tried NGK TR55.
---3 different ignition coil wires
---Opti is about a year and a half old
---ICM is about a year old
---ignition coil is MSD stock replacement.
---reseated all wires

The problem is at idle mostly. The idle is fairly rough and it feels like it is missing. Also the engine is very loud during acceleration...it isnt a normal type of loud. I have roller rockers which are loud but this "loud" is almost like I have another set of roller rockers in there. In the pitch black dark I can see an aura around 6 plugs, the ignition coil and a couple of the Opti ports. Also I can see an illumination b/w some of the wires which is probably a spark jumping from wires. The brightest illumination seems to be coming from the ignition coil but I cant tell for certain. If I give the car some throttle everything appears to go away except for the spark plug aura. Could a bad ignition coil cause these problems? Any suggestions?

 

id suggest getting your car on auto tap or something similar so you can monitor what the engine and ecm say is going on. it could be a number of things. your wires arent on there as well as you think they are, bad fuel delivery, IAC not set right. rockers not set right, clogged cat. it could be something other than ignition even though it sounds like it is. thats why i say get diagnostics done to it.

 

Done that. Everything looks good except for I am getting spontaneously misfires on multiple cylinders. I am pretty sure my brand new wires should not be lighting up and I shouldnt be seeing the "halo effect" around my coil. Would a bad coil or ground cause symptoms like I described?

 

check your grounds for sure, especially to the cylinder heads. and again i know this sounds redundant and your prolly hating me, but are you absolutely sure the wires are snapped on all the way? and did you use dielectric grease on them. im using msd 8.8 wires on my car and its easy to not put the wires onto the plug all the way, also make sure none of the ceramic insualtors on the plugs is damaged or cracked.

 

I once got a flashing SES light and thought it was my opti/wires/ etc.... chacnged wires, worked ok for couple of hours, then the same thing..... so i was like, guess its the infamous OPTI, bought a new one installed it, worked ok for a couple of hours, then the same thing..... was Pissed off!!!! It turned out to be that one of the NEW NGK's TR55 had a VERY SMALL CRACK!!!!!! after all that money that i spent it turned out to be a damn $2 spark plug!!!!!!!!

 

while you're at it check your pcv valve or egr system-these are some other problem areas on the Lt1...

 

I tried 3 totally different sets of plugs. I used dielectric grease as well as checking that the wires were snapped on. Come to find out after researching that alot of people have problems with the Taylor wires arcing. I orders some MSD 8.5 superconductors and hopefully that will resolve the issue.

 

PCV is good and I don't have EGR.

 

good luck, let us know

 

Wow.. i have the same problem.. its not your wires.. dont waste your money.. its going to do the same thing as the opti and plugs.. I dont know what the problem is.. I bought a new opti, wires(moroso ultra 40 race wires), ICM,coil, checked my ignition box, new plugs like 4 times and re ground EVERYTHING.. still does it.. I dont friggen get it. Same plugs each time though.. AutoLites.. the 103s are what im using on my car..