I have a 1995 camaro z28 and have went through 5 sets of wires in 2 months. They all flicker a blue color around the boots at the plugs. My rubber hose from the water pump weep hole also arcs when it touches metal. All sensors are good. Fuel pump and pressure and regulator also good. no codes. New ICM and coil. It runs bad when it has been running awhile. also put new battery cables on it. my question is can a bad optispark cause these problems after it gets hot. I did get a code 36 a few months ago and cleared it and it never came back. I have a snap on 2500 scanner. Also added extra grounds and that did nothing. Before I buy a new Opti I wanted to see if anyone has figured this type of problem out. Everything is stock but the magnaflow y pipe and muffler. Thanks for any ideas.

Still going

 

My last opti was in 2018 from the ebay guy that use to rebuild them but he does not anymore. He is a pilot now.

 

Have you checked the spark plug gaps? Larger gaps create excessive voltage, and can produce a blue “corona”. Corona by itself is not necessarily a problem. Are you using one specific brand of wire, or have you tried different brands? I remember many years ago Taylor used to get a bad rap on the LT1, have no idea if it was a valid concern.

 

I used different brands and even had some made from FireCore. Had ngk tr55ix gaped at .045 for many years but went back to AC delco platinum gaped at.050 . runs great till engine gets hot then it misfires and studders and have no power. I even put new oxygen sensors on it because the tailpipes were getting black smutty and smelling like gas. No gas at the regulator vacuum lines. Im assuming the misfires are causing it but new wires and plugs don't stop the misfires after it gets hot. Also changed out the injectors which came from Racetronix. The stock size. Maybe the optispark.

 

What scans or datalogs have you done? That should at least tell you something and be the best at pointing you in a direction. Some corona discharge at the plug is normal. If that is the only place you see any arcing, plug wires are likely not an issue.

 

While I'm not one to fire the parts canon without diagnostics....the stumble & misfire when car warms up is a common symptom of failing ICM. Additionally, a failing ICM can take a coil out and vice versa. IDK if either would cause corona at plug end.

I have also seen plug boot arc when using the metal boot heat shields if there is a crack in the rubber boot end.

For wires I have Magnacore wires.

 

Tried new icm AC delco and Orieley coil and a msd coil with same results. I've driven around with my snap on scanner and all the numbers looks good. Temperature looks good. New sensor. Whats weird is way is the rubber hose from my water pump weep hole arcing when it touches metal. It don't shock you to touch it.

 

Have you checked the spark plug appearance on both banks…. signs of running rich in particular? Silly question, but have to ask - have you confirmed the spark plug wiring sequence?

What is the gas mileage, city, and freeway?

Does the misfire condition worsen during days of high humidity?

Can your scanner display the A/F ratio control cell # simultaneously with left and right bank long term fuel corrections? For example, Cell 16 is the idle cell. Can the scanner produce a data log file?

With essentially no codes for the Opti (1 exception) the condition of the cap would be the most likely cause of misfires (but not the “corona”). Cracked cap, carbon tracking, etc. Is the Opti fairly clean, free of grunge? It's conceivable that the ionization due to the high voltage plug wire Corona, combined with conductive dirt/moisture buildup could be causing discharges to interfere with the pulse pattern from the two optical cam position sensors. Just an off the wall thought, but could tie in to the arcing of the water pump drain hose.

At this point, checheck the Opti harness connector for corrosion, damaged pins, etc. Check for corrosion buildup in the Opti plug and coil wire terminals.

 

All the plugs look black like soot not oil. The Firecore wires are on correct and they are numbered. I am using twice as much gas as I normally do only driving like 80 miles a day 4 days a week mostly highway. when its running good in the morning it gets better gas mileage. It runs worse at tempertures in high 80s and 90s. My scanner shows all the cells and BLMs and most other stuff but it wont create a file or log anything. Maybe I can get someone to ride along and write stuff down. Two weeks ago I put a new MSD cap and rotor on the opti but the other cap looks pretty good. The bearings had a little play in them so I had a cheap new opti with good bearing that I used but I put the mitsubishi sensor in the cheap opti base. Still it ran the same as the other opti with the play in the bearings. Maybe the sensor is the problem... Also put a new opti harness on it two weeks ago. Coil wire looks good. I checked it out 2 days ago. Don't know if this matters but although my car is a 1995 . About 7 or 8 years ago I had a guy put another engine in it. He said it was the same year engine. A Few years later I had opti problems and come to find out it had the opti with the splines on it but I never knew the difference cause all of my 1995 stuff was on it and the same computer and it ran very well. I did notice the pcv hose was different. It looked like a horse shoe shape. In 2018 I bought an opti from Brad, the Ebay guy that use to rebuild them. Come to find out I a wiring issue on my icm wiring and that was the real problem. So I still have that old Mitsubishi sensor was a working sensor and I might try swapping that sensor with the Mitsubishi sensor from Brads opti. The ebay guy. Also the problems started before I used the cheap opti base. and the rotor was clocked in the right position.

 

Check the grounds from battery to engine and chassis. It sounds to me like there is an open ground circuit somewhere, especially because of the water pump hose issue.New engine...maybe missed replacing a ground wire?

 

thanks for all the suggestions...... The engine was replaced about 8 years ago and have been running great. it just started running bad a few months ago and getting worst with the texas heat. I was on a corvette forum and a guy had a bad msd opti that was arcing everywhere and running rich while idling with the smell of gas and a new opti fixed his car. I actually put new battery cables and a extra ground to the alternator and cleaned all the stock grounds. There have been a few times that my rpms would not move after starting the car so I would turn it off and start it back up and it would work. maybe thats opti related.