No. The bank letter has to state your average balance over the last 6 months. If the bank can't confirm that in the letter, you have to submit 6 months of statements.
CIC will want to see a reason why such a large amount was added in and if it is a loan it will be rejected.
If it is a gift you will need a notorized gift certificate.
If it's a gift from family get them to write confirmation it's a gift and get it notorized.
If you sell your car now then make sure you keep proof of bill of sale/receipt.
From CIC:
Purpose
To confirm whether the applicant meets the low-income cut-off (LICO), assessed by the amount of money they hold compared to the number of people in their family
Document requirements
The applicant should provide an official letter(s) from one or more financial institutions that lists all current bank and investment accounts as well as outstanding debts, such as credit card debts and loans.
o The letter(s) must be printed on the letterhead of the financial institution and must include the applicant’s name, the contact information of the financial institution (address, telephone number and email address), the account numbers, the date each account was opened and the current balance of each account as well as the average balance for the past six months.
Other documents may also be requested, as necessary.
Individuals who must submit this documentation
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