This is REALLY starting to bug me. Truck used to idle below 300rpms and almost die. Thought it was bad gas. Then when I couldn't feather it to save it, it would die and not start. Radio clock showed 12:00 like the batter was dead. Put on volt meter, 12.25 volts or so. Jumped it, started right up. 2 days later, same issue. Took over to my bro in law who's an ASE Master Tech for Lexus, same thing, battery tested fine. Started it up, 13.69 or so volts. Shut off truck, here's where it gets nasty. Volt meter shot up to almost 20V. Yes, with the truck OFF. We thought, WTF? So we determined that the alternator might be storing some energy and the diodes were allowing volts to go OUT of it to the battery. So I changed it, used some ChemTool to clean out the top-end, cleaned out the throttle body and VIOLA problem solved. So we thought. A week later, truck died again. But, at startup. It would not start. Battery showed 12.34V but this time, the starter was clicking. So, I changed the starter. Worked fine for 4 days. Wife just called, truck is dead again. We drove it all over this weekend. From Stockton to Clear Lake and back. She took it to work, fired up no problem. It sat until she got off work and will not start and the starter is clicking. Once jumped it, it's fine.

Any suggestions?

 

Change the battery


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