The amount of tax withheld from your pay has nothing to do with your tax liability or with how much of the EV credit you can get.
The amount you owe is not your "tax liability." Your tax liability is the total tax on your income for the year, before applying any credits, withholding, or other payments. On your 2022 Form 1040 the total tax liability before nonrefundable credits is on line 18. The amount of your refund and the amount of your withholding will not affect how much of the EV credit you can get. The EV credit is a nonrefundable credit. Nonrefundable credits are applied to your total tax liability for the year, not to the amount that you owe when you file your tax return.
The nonrefundable credits are not applied in any particular order. They are all added together. The total nonrefundable credits, including the EV credit, are on Form 1040 line 21. On line 22 the total nonrefundable credits on line 21 are subtracted from the total tax liability on line 18, but the result cannot be less than zero. If the total nonrefundable credits on line 21 are more than the total tax liability on line 18, then you are not able to use all the nonrefundable credits, and line 22 will be zero. But it's not any one particular credit that is reduced. It's the total of all the credits that is limited.
If Form 1040 line 22 is not zero, you are using the full amount of all your nonrefundable credits.
Withholding is subtracted later, on Form 1040 line 25a. It does not affect the amount of nonrefundable credits that you can use on line 22.
