Is Zakat obligatory on the car installment amount deducted monthly from the salary, and is Zakat obligatory on the car itself?

There is no zakat on the amount deducted by the bank. Zakat is obligatory on what remains if it reaches the nisab and a full year has passed over it.

Regarding the car: - If it is for personal use, there is no zakat on it. - If it is intended for trade, then it is subject to zakat as trade goods by valuation, and zakat becomes obligatory on it if its value reaches the nisab by itself or when combined with other money or trade goods, and a full year has passed over it. - If it is for rent, zakat is obligatory on the remaining rental income if it reaches the nisab or completes the nisab of other assets.