No. It only affects weapon attacks.
I assume you're using the Improved Pact Weapon invocation from Xanathar's Guide to Everything to use your pact weapon as your spellcasting focus, and also choosing that type of weapon as a kensei weapon for the Path of the Kensei feature.
The description of Improved Pact Weapon:
You can use any weapon you summon with your Pact of the Blade feature as a spellcasting focus for your warlock spells. In addition, the weapon gains a +1 bonus to its attack and damage rolls, unless it is a magic weapon that already has a bonus to those rolls. Finally, the weapon you conjure can be a shortbow, longbow, light crossbow, or heavy crossbow.
However, Jeremy Crawford has stated (and Mike Mearls has agreed) that the pact weapon bonus only applies to its weapon attacks, not to spell attacks that use it as a focus:
The bonus to attack rolls conferred by Improve Pact Weapon applies to the weapon's attack rolls, not to a spell's attack rolls.
Similarly, only the ranged weapon attacks made with your kensei weapon itself would count for the Kensei Shot bonus damage - spell attacks that use the weapon as a focus (substituting for a material component) wouldn't qualify. Crawford essentially confirms this here in response to a question about making a spell attack with an Improved Pact Weapon as a focus:
Using a weapon as a material component for a spell, including as a spellcasting focus, doesn't count as attacking with that weapon, unless the spell explicitly says you attack with it.
Using a weapon as a spellcasting focus doesn't count as attacking with the weapon. You're channeling magic through the weapon; you're not striking with it.