Car stutters when first started and driving

I have a 2001 Infiniti I30, 106000 miles. I had the regular services performed and am noticing the car hesitating when I first start and take off.After a minute it runs fine and has no more problems and rpms are fine and steady. I had the sparkplugs changed @99k. I tried pulling codes no luck, tried seafoam no luck, checked battery and hoses nothing. Any help is appreciated

How is the fuel pressure? Check it from cold start.

Check out the coolant temperature sensor.