diff --git a/src/MIMEWriter.php b/src/MIMEWriter.php
index dc90d58..53086fb 100644
--- a/src/MIMEWriter.php
+++ b/src/MIMEWriter.php
@@ -322,8 +322,10 @@ protected function createMultipartBoundaryName(string $prefix): string
      */
     protected function escapeHeaderValue(string $value): string
     {
+        $quoted_value = quoted_printable_encode($value);
+        $quoted_value = str_replace("=\x0d\x0a",'', $quoted_value);
         return preg_match('/[\x80-\xFF]/', $value) === 1
-            ? "=?UTF-8?Q?" . quoted_printable_encode($value) . "?="
+            ? "=?UTF-8?Q?" . $quoted_value . "?="
             : $value; // as-is
     }
 
diff --git a/tests/TestMessageFactory.php b/tests/TestMessageFactory.php
index cea7b36..d01cd84 100644
--- a/tests/TestMessageFactory.php
+++ b/tests/TestMessageFactory.php
@@ -218,7 +218,7 @@ public function createMessageWithCustomHeaders(): Message
         $message = new Message(
             new Address("blip@test.org"),
             new Address("blub@test.org"),
-            "Hey, Rasmus!",
+            "We need a special character - Ø - so that quoted_printable_encode is used, and more than 75 characters - see documentation for quoted_printable_encode()",
             "Hello!"
         );
 
diff --git a/tests/unit/MIMEWriterCest.php b/tests/unit/MIMEWriterCest.php
index 90935dd..06fe48b 100644
--- a/tests/unit/MIMEWriterCest.php
+++ b/tests/unit/MIMEWriterCest.php
@@ -341,7 +341,7 @@ public function writeMessageWithCustomHeaders(UnitTester $I): void
             Date: Thu, 15 Sep 2016 17:20:54 +0200
             To: blip@test.org
             From: blub@test.org
-            Subject: Hey, Rasmus!
+            Subject: =?UTF-8?Q?We need a special character - =C3=98 - so that quoted_printable_encode is used, and more than 75 characters - see documentation for quoted_printable_encode()?=
             MIME-Version: 1.0
             X-Custom-Header: custom-value
             Content-Type: text/plain; charset=UTF-8