Spenj0rk
Newbie
I have this 91 c1500 that is giving me a fit.
Problem:
Dim fast flashing CEL and really high idle. I have replaced distributor, set timing, replaced bad vacuum hoses, installed new IAC, CTS, TBS, cleaned all ground cables, repaired bad wires, pulled ecm, cleaned terminals and reset PROM. as soon as you start it, it idles a little high like it should. The engine light faintly flashing very fast then the idle shoots up to around 2k rpms. Then, one day it will run perfect with no CEL light on. Then the next day I have the same problem with fast idle and flashing CEL. When jumping A&B I get code 12x3 then code 15 but I have replaced the CTS. Any help would be great.
Problem:
Dim fast flashing CEL and really high idle. I have replaced distributor, set timing, replaced bad vacuum hoses, installed new IAC, CTS, TBS, cleaned all ground cables, repaired bad wires, pulled ecm, cleaned terminals and reset PROM. as soon as you start it, it idles a little high like it should. The engine light faintly flashing very fast then the idle shoots up to around 2k rpms. Then, one day it will run perfect with no CEL light on. Then the next day I have the same problem with fast idle and flashing CEL. When jumping A&B I get code 12x3 then code 15 but I have replaced the CTS. Any help would be great.