Hey everyone! Just registered here and love finding people that still have their older blazers. Brief history: back in '85, my grandparents bought the brand new s10 blazer Tahoe. I thought it was the coolest thing Ive ever seen. (Still do). Many memories growing up with this car. About 18 years ago, I bought it from my grandparents and they purchased a '98 blazer which is still going strong. Anyways, I love my '85. Yes it's had it's share of problems, but what car doesn't. I try to keep up with basic maintance as to avoid other bigger problems , and do most of the work myself as my experience level hovers right around "Novice". Lately the blazers been trying to die on me while idling. This happens a couple times a day. The last couple times I felt it was trying to quit on me, I noticed I was running hot, and after filling back up a very thirsty radiator, the problem seemed to stop. But now it's back again with some new strange signs. Yesterday after noticing it was chugging, I popped the hood with it running and noticed a bright intermitent spark coming from some wires back near the firewall. The spark would happen about every 2 to 3 seconds and lasted about a half a second. I need to do some further investigating as to what the wires control when I get some free time, but wanted to see if anyone else has experienced anything similar. Any help would be very much appreciated.

 

Sounds like a spark form the ignition.

Spark intermittent erratic or in a regular interval?

Regular interval could point to a broken ignition wire. (Don't touch while present)
With everything shut down you may want to trace all the ignition wires and search for damage, scuffing, broken insulation.

A broken ignition wire which sparks to ground somewhere will have that cylinder miss (not fire) which may explain the "nearly dying in idle".