File upload error cakephp

When I choose an image and push upload, I get this error in my controller:
Notice (8): Undefined index: File [APP/controllers/garage_car_images_controller.php, line 22]

I've also noticed that the $form->create line shown below does NOT generate form code in the inspected html. This is VERY weird.

Any ideas how to fix this? Thanks!

My view code:

add image

<?php echo $form->create('GarageCarImage', array('controller' => 'garage_car_images','action' => 'add', 'type' => 'file')); echo $form->file('File'); echo $form->hidden('garage_car_id', array('value' => $this->params['pass'][0])); echo "

"; echo "Make this image the default? " . $form->input('default', array('type' => 'select', 'label' => false, 'options' => array('0' => 'No', '1' => 'Yes'))); echo "
"; echo $form->submit('Upload'); echo $form->end(); ?>

My controller code:

if (!empty($this->data) &&
             is_uploaded_file($this->data['GarageCarImage']['File']['tmp_name'])) {
            $fileData = fread(fopen($this->data['GarageCarImage']['File']['tmp_name'], "r"),
                                     $this->data['GarageCarImage']['File']['size']);

            $this->data['GarageCarImage']['type'] = $this->data['GarageCarImage']['File']['type'];
            $this->data['GarageCarImage']['user_id'] = $this->Auth->user('id');
            $this->GarageCarImage->save($this->data);
}