make much of an impression

[Maybo]

The other actors don’t make much of an impression. (Going to Pains for Love in a Flashy Urban Jungle By Rachel Saltz)

Can I say "...make much impression"?

[GoesStation]

No.

[Maybo]

Why is "of" needed here?
Sometimes I don't know when to use "of"
For example, we say " it doesn't make sense" but not "it doesn't make much of sense"

[jutfrank]

Think of this as an example of the semi-fixed phrase [not] much of a. The meaning is something similar to 'to a small extent', which I presume is clear enough from the context you've provided.

Since the final word of this phrase is an indefinite article, the following word must be a singular countable noun.

[Phaedrus]

The other actors don’t make much of an impression.

Why is "of" needed here? . . . For example, we say " it doesn't make sense" but not "it doesn't make much of sense"

"Of" is used when the noun phrase following "much" is an indefinite noun phrase headed by a count noun:

(1a) It isn't much of a problem.
(1b) *It isn't much problem.

"Of" is not used between "much" and the following noun phrase when that noun phrase is an indefinite noun phrase headed by a noncount noun:

(2a) *It isn't much of trouble.
(2b) It isn't much trouble.