I have two issues I'm trying to solve with my '93 Full Size Blazer (5.7L). Any thoughts would be greatly appreciated.
1. The truck will stall at a stoplight when the engine is hot unless I put the vehicle in neutral or take my foot off the brake and let the vehicle roll/creep forward. The engine/ignition seems to "time itself" into a stall. My thought is to install a new distributor assembly (currently has 280k miles on original unit) thinking the ignition control module might be bad. Interestingly, the blazer runs fine for the first couple of stop-lights in the morning, until she gets hot.
2. The Air Conditioning blower motor will not come on when the outside temp is hot. I hear the relays clicking behind the glove-box, but the fan will not come on. If I slam the driver or passenger door, this sometimes kicks the blower on. I removed the glove-box liner and swapped the 3 Hella Relays around in various combinations, but still, no operational blower fan. What else would make the Air conditioning fan motor fail during days of average to high outside temps ?
Regards,
Keith

 

1) I'll bet that you need to clean the throttle body. When you pull the air cleaner off, look down at the butterfly plate... does it look dirty around the edges to where it may not be closing completely? Grab some eye protection and a can of throttle plate cleaner and get to work... also be sure to remove and clean the Idle Air Controller.

2) Grab a test light and start checking connections... especially grounds. Really sounds to me like you may have a bad connection or two.