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Cars is jumpy when taking off after starting

2001 Infiniti I30 105000 miles, had the sparkplugs changed 5k ago.

When I start the car and take off, it pulsates/ minor jumping for the first minute then works it self out and runs fine.Any ideas would help thanks

Is the Check Engine Light illuminated?

No - the check engine light is not illuminated.

Could it be a transmission problem? When you say it jumps, that could be hard shifts, or early or late shifts, or a slipping transmission. What do your RPMs look like if you hold the gas steady. If they fluctuate a lot, it could be an engine problem, but I don’t know what kind of engine problem would not trip the CEL. Which is why I’m thinking trans. Can you guess from the symptoms whether it seems to be the engine or the trans?

Many auto parts stores will let you plug a code reader into the computer for free and read out any stored codes. You may have a code even if the CEL is not on.

Here’s another slightly random thought? Have you checked your coolant level? If the coolant is low, it might not cover the coolant temp sensor, so the car is not getting the right info on whether the engine is warmed up, which will affect the fuel mix and idle speed. As the engine warms up, the coolant expands and eventually covers the sensor, so it runs ok after that. (I had a Ford Contour that did this until I added more coolant.)

I was worried it might be the tranny.There is no hesitation when at a light or after it runs for about a minute.
I will try the Code puller a buddy ahs one. The rpms hold steady at all speeds.
Could it be the fuel pump or filter might take a second to flow correctly?
I will put more Anti-freeze in I noticed it was on the low side last time I changed the oil.
Thanks for the help!