× Auto Repair Pros Member Benefits TechHelp Knowledge Base Forums Resources My iATN Marketplace Chat Pricing About Us Join Industry Sponsors Video Members Only Repair Shops Auto Pro Careers Auto Pro Reviews
Join Now
International Automotive Technicians Network
Re: GM Code 42 (Electronic Spark Timing)
Posted to Technical Discussion Forum on 2/14/1998 4 Replies

Thanks Danny. You beat me to the punch. I had the same idea for evaluating the EST/Bypass lines. Good show! Miles' second pic had almost convinced me, too, that the ECM was at fault. My only hang up is, as you've pointed out, the fact that the EST signal does ... Login to read more.

4 Replies Received (View Replies)