Truck bogs down only when taking off on cool engine

My pickup hesitates when I take off in the morning or after it has been sitting long enough for the engine to cool down. It acts as if its not getting fuel, is ok when I back off the throttle, and will backfire if I stay on it. After about 2-3 minutes its fine. Mechanic has researched and replaced several items to no avail. Initially it was doing this and the check engine light would come on. The check engine light came on one day after the last time the shop took a look at it and then the next day it went back off (or burned out). I’m wondering if anybody else has had this experience?

way too wide open.

need year, engine, trans info. what parts replaced. what codes prompted the replacements.

first pass sounds like cold start scheme in computer. ECT comes to mind.

mechanic should keep car till it cools off and then run from cold start with scanner attached. If ECT bad, engine may think already warm, but it’s not.

its a 97, 318, automatic. I’ll round up the other info and post it later today or in the morning. Thanks for the response, this is an annoying part of what has been a really good experience with this truck.

People draw too many false conclusions when a check engine light is on but suddenly goes out,like the car healed its self.