3rd gen 5.4L issues

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ManUpOrShutUp

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On a cold start, I have a normal crank and the engine starts right up. On a warm start, the crank continues for 1-2s after the engine starts up. I have also noticed my long fuel trims creeping up. While idling or very low throttle, they're as they always were. Give it some gas and they run +6.x/+7.x. That isn't out of range, but is it unusual for my truck, which for years ran +3.x/4.x under the same conditions. My gas mileage has dropped a little bit as well going from high 15s to high 13s with mostly highway driving. Engine temps occasionally and breifly drop below normal operating temp if I'm going really easy on her about town (not the tstat), but this issue started 20k miles ago after a mechanic replaced the intake manifold gaskets so I have no reason to think it's related. No TC/pending TC. No new drivability issues (208k on the clock, so it hasn't exactly purred for years). Fuel pump/filter? ECT sensor? Something else?
 

bodabdan

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Things I would look at-
Smoke test for vacuum leaks, oxygen sensor deterioration (I change them at 100k), fuel quality, ECT/IAT accuracy, MAF cleanliness, IAC performance, and if injectors haven't been professionally cleaned they might be ready.
 
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