If I want to instantiate an object, but don't know whether I have a Sedan or an SUV, can I ask the base class to figure that out for me and return the right object?

You certainly can.

Is that good practice?

This probably debatable. From a theoretical perspective, a parent class should not depend on its child classes, just the other way. Or formulated differently, you want to avoid cycles in your dependency graphs.

From a practical point of view, there often needs to be some piece of code that needs to create as-specific-as-possible objects. Why not have put it in the parent class?

An approach I found practical is to have some kind of "type registry", which is usually just a hash. On object creation, some kind of key looks into the hash, and then simply re-dispatches to new method of that type.

package Car;

has %car_by_type;

sub new {
   my ($self, %opts) = @_;
   if ($opts{name} && $car_by_type{$opts{name}}) {
      $car_by_type{$opts{name}}->new(%opts);
   }
   else {
      die "Don't know how to make a new car";
   }
}

method REGISTER_TYPE {
    my ($self, $name, $type) = @_;
    $car_by_type{$name} = $type;

}

package Car::BMW;
our @ISA = qw/Car/;
Car::BMW->REGISTER_TYPE('Z1', __PACKAGE__);
Car::BMW->REGISTER_TYPE('Z3', __PACKAGE__);

package main;
my $z1 = Car->new(name => 'Z1');
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(untested)