The complaint is the engine dies (stalls) after the battery failed and after battery replacement.
The first thing comes to my mind is an idle control problem. The trucks engine computer has been adapting programming as needed to compensate for wear and age conditions. When the battery power is lost so is the adaptive programming. Commonly the throttle bore and plate have been building over time a layer of carbon. Because this happened slowly the computer was able to make changes in idle control strategy and maintain idle. The loss of battery power reverted the system back to factory settings and since there was no carbon then, the settings aren't correct for maintaining idle now. If this is the problem then I should see the stalling being related to a slow idle speed and a slow response to an rpm drop at idle.
You can see the idle drop to a near stall in this pic when I place the shifter from park to reverse. The iac counts are a rough indicator of how hard the iac is working to maintain idle speed. You can see iac is slow to respond to the rpm drop. So there is probably a carbon problem.
You have to get in there with a rag and some cleaner. Hold the throttle plate open and wipe the area clean.
Now after reassembly we start the engine to clear any excess cleaner and let the idle stabilize. Look now how quickly the iac responds and how easily it maintains idle rpm as I move the shifter this time.
A test of alternator and battery draw and this truck is fixed.
Kenneth Hayes
G&G Auto Repair
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