diff --git a/src/CsvReader.php b/src/CsvReader.php
index 795fef3..2dda6ee 100644
--- a/src/CsvReader.php
+++ b/src/CsvReader.php
@@ -103,7 +103,11 @@ public function fetchAllAssoc(array $keys = array())
 
         $data = array();
 
+        $rowCounter = 0;
+
         while ($row = $this->getNextRow()) {
+            $rowCounter++;
+
             if ($headerFlag) {
                 $headerFlag = false;
                 $keys = $this->negotiateEncoding($row);
@@ -112,7 +116,10 @@ public function fetchAllAssoc(array $keys = array())
             }
 
             if (count($row) !== $keysCount) {
-                throw new Exception('Malformed line in CSV input');
+                throw new Exception(sprintf(
+                    'Malformed row (%s) in CSV input',
+                    $rowCounter
+                ));
             }
 
             $data[] = array_combine($keys, $this->negotiateEncoding($row));
@@ -128,19 +135,17 @@ public function fetch()
     {
         $row = $this->getNextRow();
 
-        if (false === $row) {
-            // EOF
-            return false;
+        if (is_array($row)) {
+            $row = $this->negotiateEncoding($row);
         }
 
-        $row = $this->negotiateEncoding($row);
-
         return $row;
     }
 
     /**
      * @param array $keys
      * @return array|bool
+     * @throws Exception
      */
     public function fetchAssoc(array $keys = array())
     {
@@ -165,6 +170,13 @@ public function fetchAssoc(array $keys = array())
 
         $this->fetchRowLineCounter++;
 
+        if (count($row) !== count($this->fetchRowKeys)) {
+            throw new Exception(sprintf(
+                'Malformed row (%s) in CSV input',
+                $this->fetchRowLineCounter
+            ));
+        }
+
         return array_combine($this->fetchRowKeys, $this->negotiateEncoding($row));
     }
 
@@ -177,10 +189,6 @@ private function getNextRow()
 
         $tmp = fgetcsv($this->stream, 0, $this->delimiter, $this->enclosure, $this->escape);
 
-        if ($tmp !== false && !is_array($tmp)) {
-            throw new LogicException('Unexpected error in fgetcsv call');
-        }
-
         return $tmp;
     }
 
diff --git a/tests/Kaloa/Tests/Filesystem/CsvReaderTest.php b/tests/Kaloa/Tests/Filesystem/CsvReaderTest.php
index 8edef62..04a4b3d 100644
--- a/tests/Kaloa/Tests/Filesystem/CsvReaderTest.php
+++ b/tests/Kaloa/Tests/Filesystem/CsvReaderTest.php
@@ -73,7 +73,6 @@ public function testCanReadWithOnlyHeaders()
         $expected = array();
 
         $this->assertSame($expected, $data);
-
     }
 
     /**
@@ -93,6 +92,23 @@ public function testCanReadWithoutHeaders()
         $this->assertSame($expected, $data);
     }
 
+    /**
+     *
+     */
+    public function testCanReadWithCustomHeaders()
+    {
+        $stream = fopen(__DIR__ . '/csv-files/no-headers.csv', 'rb');
+        $reader = new CsvReader($stream);
+        $data = $reader->fetchAllAssoc(array('Col a', 'Col b'));
+        fclose($stream);
+
+        $expected = array();
+        $expected[] = array('Col a' => 'value 1a', 'Col b' => 'value 1b');
+        $expected[] = array('Col a' => 'value 2a', 'Col b' => 'value 2b');
+
+        $this->assertSame($expected, $data);
+    }
+
     /**
      *
      */
@@ -199,18 +215,68 @@ public function testThrowsExceptionOnInvalidStream()
         new CsvReader('invalid');
     }
 
+    /**
+     *
+     */
+    public function testThrowsExceptionOnMalformedLine()
+    {
+        $csvData = <<<'CSV'
+"Col a","Col b"
+"value 1a"
+"value 2a","value 2b"
+CSV;
+
+        $dataUri = $this->convertToDataUri($csvData);
+
+        $stream = fopen($dataUri, 'rb');
+
+        $reader = new CsvReader($stream);
+
+        $this->setExpectedException('Exception', 'Malformed row (2) in CSV input');
+
+        $reader->fetchAllAssoc();
+
+        fclose($stream);
+    }
+
+    /**
+     *
+     */
+    public function testThrowsExceptionOnMalformedLineInStreamingMode()
+    {
+        $csvData = <<<'CSV'
+"Col a","Col b"
+"value 1a"
+"value 2a","value 2b"
+CSV;
+
+        $dataUri = $this->convertToDataUri($csvData);
+
+        $stream = fopen($dataUri, 'rb');
+
+        $reader = new CsvReader($stream);
+
+        $this->setExpectedException('Exception', 'Malformed row (2) in CSV input');
+
+        while ($row = $reader->fetchAssoc()) {
+            // nop
+        }
+
+        fclose($stream);
+    }
+
     /**
      *
      */
     public function testCanConvertCharset()
     {
         $csvData = <<<CSV
-"Thomas Müller","FC Bayern München",Sturm
-"Julian Weigl","Borussia Dortmund",Mittelfeld
-"Serge Gnabry","Werder Bremen",Sturm
-"Gianluigi Buffon",Juventus,Tor
-"Shkodran Mustafi",Arsenal,Abwehr
-"Mario Gómez","VfL Wolfsburg",Sturm
+"Thomas Müller","FC Bayern München",Striker
+"Julian Weigl","Borussia Dortmund",Midfield
+"Serge Gnabry","Werder Bremen",Striker
+"Gianluigi Buffon",Juventus,Keeper
+"Shkodran Mustafi",Arsenal,Defender
+"Mario Gómez","VfL Wolfsburg",Striker
 CSV;
 
         $csvData = mb_convert_encoding($csvData, 'ISO-8859-1', 'UTF-8');
@@ -232,10 +298,10 @@ public function testCanConvertCharset()
 
         fclose($stream);
 
-        $expected = array('name' => 'Thomas Müller', 'team' => 'FC Bayern München', 'position' => 'Sturm');
+        $expected = array('name' => 'Thomas Müller', 'team' => 'FC Bayern München', 'position' => 'Striker');
         $this->assertSame($expected, $data[0]);
 
-        $expected = array('name' => 'Mario Gómez', 'team' => 'VfL Wolfsburg', 'position' => 'Sturm');
+        $expected = array('name' => 'Mario Gómez', 'team' => 'VfL Wolfsburg', 'position' => 'Striker');
         $this->assertSame($expected, $data[5]);
     }
 
@@ -257,7 +323,7 @@ public function testFetchAllAfterEofReturnsEmptyArray()
     }
 
     /**
-     * @param $string
+     * @param string $string
      * @return string
      */
     private function convertToDataUri($string)