diff --git a/lib/stringify.js b/lib/stringify.js
index b8cee4bc..fa329304 100644
--- a/lib/stringify.js
+++ b/lib/stringify.js
@@ -19,6 +19,7 @@ var arrayPrefixGenerators = {
 };
 
 var isArray = Array.isArray;
+var split = String.prototype.split;
 var push = Array.prototype.push;
 var pushToArray = function (arr, valueOrArray) {
     push.apply(arr, isArray(valueOrArray) ? valueOrArray : [valueOrArray]);
@@ -102,6 +103,14 @@ var stringify = function stringify(
     if (isNonNullishPrimitive(obj) || utils.isBuffer(obj)) {
         if (encoder) {
             var keyValue = encodeValuesOnly ? prefix : encoder(prefix, defaults.encoder, charset, 'key', format);
+            if (generateArrayPrefix === 'comma' && encodeValuesOnly) {
+                var valuesArray = split.call(String(obj), ',');
+                var valuesJoined = '';
+                for (var i = 0; i < valuesArray.length; ++i) {
+                    valuesJoined += (i === 0 ? '' : ',') + formatter(encoder(valuesArray[i], defaults.encoder, charset, 'value', format));
+                }
+                return [formatter(keyValue) + '=' + valuesJoined];
+            }
             return [formatter(keyValue) + '=' + formatter(encoder(obj, defaults.encoder, charset, 'value', format))];
         }
         return [formatter(prefix) + '=' + formatter(String(obj))];
@@ -124,8 +133,8 @@ var stringify = function stringify(
         objKeys = sort ? keys.sort(sort) : keys;
     }
 
-    for (var i = 0; i < objKeys.length; ++i) {
-        var key = objKeys[i];
+    for (var j = 0; j < objKeys.length; ++j) {
+        var key = objKeys[j];
         var value = typeof key === 'object' && key.value !== undefined ? key.value : obj[key];
 
         if (skipNulls && value === null) {
diff --git a/test/stringify.js b/test/stringify.js
index fcbec285..9750594e 100644
--- a/test/stringify.js
+++ b/test/stringify.js
@@ -134,8 +134,7 @@ test('stringify()', function (t) {
     t.test('stringifies a nested array value', function (st) {
         st.equal(qs.stringify({ a: { b: ['c', 'd'] } }, { encodeValuesOnly: true, arrayFormat: 'indices' }), 'a[b][0]=c&a[b][1]=d');
         st.equal(qs.stringify({ a: { b: ['c', 'd'] } }, { encodeValuesOnly: true, arrayFormat: 'brackets' }), 'a[b][]=c&a[b][]=d');
-        st.equal(qs.stringify({ a: { b: ['c', 'd'] } }, { encodeValuesOnly: true, arrayFormat: 'comma' }), 'a[b]=c%2Cd');
-        st.equal(qs.stringify({ a: { b: ['c', 'd'] } }, { encodeValuesOnly: true, arrayFormat: 'comma' }), 'a[b]=c,d', '(pending issue #378)', { skip: true });
+        st.equal(qs.stringify({ a: { b: ['c', 'd'] } }, { encodeValuesOnly: true, arrayFormat: 'comma' }), 'a[b]=c,d');
         st.equal(qs.stringify({ a: { b: ['c', 'd'] } }, { encodeValuesOnly: true }), 'a[b][0]=c&a[b][1]=d');
         st.end();
     });
@@ -157,22 +156,13 @@ test('stringify()', function (t) {
             'a.b[]=c&a.b[]=d',
             'brackets: stringifies with dots + brackets'
         );
-        st.equal(
-            qs.stringify(
-                { a: { b: ['c', 'd'] } },
-                { allowDots: true, encodeValuesOnly: true, arrayFormat: 'comma' }
-            ),
-            'a.b=c%2Cd',
-            'comma: stringifies with dots + comma'
-        );
         st.equal(
             qs.stringify(
                 { a: { b: ['c', 'd'] } },
                 { allowDots: true, encodeValuesOnly: true, arrayFormat: 'comma' }
             ),
             'a.b=c,d',
-            'comma: stringifies with dots + comma (pending issue #378)',
-            { skip: true }
+            'comma: stringifies with dots + comma'
         );
         st.equal(
             qs.stringify(
@@ -237,8 +227,8 @@ test('stringify()', function (t) {
         st.equal(
             qs.stringify({ a: [{ b: 1 }, 2, 3] }, { encodeValuesOnly: true, arrayFormat: 'comma' }),
             '???',
-            'brackets => brackets (pending issue #378)',
-            { skip: true }
+            'brackets => brackets',
+            { skip: 'TODO: figure out what this should do' }
         );
         st.equal(
             qs.stringify({ a: [{ b: 1 }, 2, 3] }, { encodeValuesOnly: true }),
@@ -845,7 +835,12 @@ test('stringify()', function (t) {
         st.equal(qs.stringify(withArray, { encode: false }), 'a[b][0][c]=d&a[b][0][e]=f', 'array, no arrayFormat');
         st.equal(qs.stringify(withArray, { encode: false, arrayFormat: 'bracket' }), 'a[b][0][c]=d&a[b][0][e]=f', 'array, bracket');
         st.equal(qs.stringify(withArray, { encode: false, arrayFormat: 'indices' }), 'a[b][0][c]=d&a[b][0][e]=f', 'array, indices');
-        st.equal(qs.stringify(withArray, { encode: false, arrayFormat: 'comma' }), '???', 'array, comma (pending issue #378)', { skip: true });
+        st.equal(
+            qs.stringify(withArray, { encode: false, arrayFormat: 'comma' }),
+            '???',
+            'array, comma',
+            { skip: 'TODO: figure out what this should do' }
+        );
 
         st.end();
     });