diff --git a/googleapiclient/http.py b/googleapiclient/http.py
index e842bb4..5e582cf 100644
--- a/googleapiclient/http.py
+++ b/googleapiclient/http.py
@@ -28,9 +28,7 @@
 from six import BytesIO, StringIO
 from six.moves.urllib.parse import urlparse, urlunparse, quote, unquote
 
-import base64
 import copy
-import gzip
 import httplib2
 import json
 import logging
@@ -38,7 +36,6 @@
 import os
 import random
 import socket
-import sys
 import time
 import uuid
 
@@ -190,11 +187,16 @@
             exception = connection_error
         except socket.error as socket_error:
             # errno's contents differ by platform, so we have to match by name.
+            # Some of these same errors may have been caught above, e.g. ECONNRESET *should* be
+            # raised as a ConnectionError, but some libraries will raise it as a socket.error
+            # with an errno corresponding to ECONNRESET
             if socket.errno.errorcode.get(socket_error.errno) not in {
                 "WSAETIMEDOUT",
                 "ETIMEDOUT",
                 "EPIPE",
                 "ECONNABORTED",
+                "ECONNREFUSED",
+                "ECONNRESET",
             }:
                 raise
             exception = socket_error
diff --git a/tests/test_http.py b/tests/test_http.py
index 9bfae93..f87d7e1 100644
--- a/tests/test_http.py
+++ b/tests/test_http.py
@@ -174,10 +174,10 @@
             # set errno to a non-retriable value
             try:
                 # For Windows:
-                ex.errno = socket.errno.WSAECONNREFUSED
+                ex.errno = socket.errno.WSAEHOSTUNREACH
             except AttributeError:
                 # For Linux/Mac:
-                ex.errno = socket.errno.ECONNREFUSED
+                ex.errno = socket.errno.EHOSTUNREACH
             # Now raise the correct timeout error.
             raise ex