I have researched this topic but could not find any info to help me. The Problem/question i have is, why does the truck start in open loop, then fuel system status goes to "non stoich" then finally to closed loop. When it enters this "non Stoich" the fuel trims start trying to take it to Lambda yet its commanding .8ish. During this time the engine will surge in rpm, go down and up, until if finally levels out. the log attached clearly shows the fuel trims going negative and the rpm surge. In the tune you can see for the ECT its calling for 130 sec of delay and that's about how long it takes to get into closed loop, but instead of staying in open loop it goes to this "Non Stoich" area after a few seconds after starting.
Anyone have any advice on this? Its kinda embarrassing having a nice running supercharged and cammed truck that runs great normally, start and surge like that.
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