I did a full tune up and purchased 2 used (working)j109 ignitors from the junkyard. A few weeks ago I noticed my car would change idle once warmed up fully and run rich with a misfire. After I installed the 1st ignitor it ran good for about a week and then popped it. So I put the second one on and it lasted about 2 weeks before going bad. My question is are the j109 ignitors this unreliable or is there something else that could possibly be causing my car to blow ignitors? Both ignitors had fresh dielectric grease applied before installation.

 

Okay I think I may have figured it out I traced the ignitor wiring back and had two wires that were touching.

 

Your statement “both igniters had fresh dielectric grease applied” may be a clue to failure.
Thermal paste which is what should be used and dielectric grease are two different compounds with different applications.
Dielectric grease is meant to be used to insulate high current leakage,ie spark plug boots,coil terminal boots.
Also used to waterproof electrical connectors. It has no heat transfer capabilities.
Thermal paste as used on FB igniters and in the computer industry is the conveyance of heat transfer from the component generating heat to heat sink to which heat generated by component is released to heat sink to allow component to cool itself and operate within designed temperature.
OP states he may have found a wire(s) responsible for igniter failure. If that is the case,that’s a good find.
Recommend removing igniters and cleaning them and distributor body of dielectric compound and applying thermal paste to back side of igniter to insure against heat related failure.

 

Thank you, I am up and running again. Interestingly enough the ignitor wasn't faulty it was the dielectric grease causing problems.

 

Can you share how you came to this conclusion?

 

I pulled the ignitor off and cleaned it and applied thermal paste, hooked everything up and turned the car over. It had a noticable misfire before with the dielectric grease. It was gone after I put it back on with the thermal paste. To make sure i let it run and did a lengthy drive.