89 S-10 2.5L 125,000. When do you know it is time to replace the ECM (on-board computer). The certified mech whom I trust thinks it is time. Long story short, I replaced everthing I could. I have a different running truck after each start, idle high, idle low, stall, black smoke, SES light, and sometimes runs perfect. Please help if you can. Oh yeah, After my engine was rebuilt 20,000 miles ago, you can't read codes.
Mar 21, 2008 at 1:47 PM