Alfa Romeo Forums banner
1 - 1 of 1 Posts

·
Trained (ex)Professional, , 1953-2018 RIP
Joined
·
16,232 Posts
...but I discovered that when I pulled the #4 wire and held it to the end of the plug forcing to arc, the cylinder would run smoothly. Put it back on and it doesn't. What does this mean?
This is a (fairly) common diagnostic technique called gapping the coil (or wire gapping the plug in this case). It forces the coil to output maximum voltage as opposed to the low voltage requirment needed to fire the plug at idle. Your symptom could indicate either a bad plug or an excessively lean/rich mixture in that cylinder.
 
1 - 1 of 1 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top