diff --git a/packages/ember-simple-auth/src/authenticators/oauth2-password-grant.ts b/packages/ember-simple-auth/src/authenticators/oauth2-password-grant.ts
index 5edb787b9..1a67bb2b5 100644
--- a/packages/ember-simple-auth/src/authenticators/oauth2-password-grant.ts
+++ b/packages/ember-simple-auth/src/authenticators/oauth2-password-grant.ts
@@ -374,7 +374,7 @@ export default class OAuth2PasswordGrantAuthenticator extends BaseAuthenticator
     @protected
   */
   @waitFor
-  makeRequest(
+  async makeRequest(
     url: string,
     data: MakeRequestData,
     headers: Record<string, string> = {}
@@ -405,26 +405,21 @@ export default class OAuth2PasswordGrantAuthenticator extends BaseAuthenticator
       method: 'POST',
     };
 
-    return new Promise((resolve, reject) => {
-      fetch(url, options)
-        .then(response => {
-          response.text().then(text => {
-            try {
-              let json = JSON.parse(text);
-              if (!response.ok) {
-                (response as OAuth2Response).responseJSON = json;
-                reject(response);
-              } else {
-                resolve(json);
-              }
-            } catch (SyntaxError) {
-              (response as OAuth2Response).responseText = text;
-              reject(response);
-            }
-          });
-        })
-        .catch(reject);
-    });
+    const response = await fetch(url, options);
+    const text = await response.text();
+    const cloned = response.clone() as OAuth2Response;
+    try {
+      const json = JSON.parse(text);
+      if (response.ok) {
+        return json;
+      } else {
+        cloned.responseJSON = json;
+        throw cloned;
+      }
+    } catch (SyntaxError) {
+      cloned.responseText = text;
+      throw cloned;
+    }
   }
 
   _scheduleAccessTokenRefresh(
diff --git a/packages/test-esa/tests/unit/authenticators/oauth2-password-grant-test.js b/packages/test-esa/tests/unit/authenticators/oauth2-password-grant-test.js
index 924f67ef1..8853ccd45 100644
--- a/packages/test-esa/tests/unit/authenticators/oauth2-password-grant-test.js
+++ b/packages/test-esa/tests/unit/authenticators/oauth2-password-grant-test.js
@@ -318,6 +318,17 @@ module('OAuth2PasswordGrantAuthenticator', function (hooks) {
         }
       });
 
+      test('rejects with original/cloned response', async function (assert) {
+        assert.expect(1);
+        try {
+          await authenticator.authenticate('username', 'password');
+          assert.ok(false, "Mustn't reach here. Test failed.");
+        } catch (response) {
+          const json = await response.json();
+          assert.deepEqual(json, { error: 'invalid_grant' });
+        }
+      });
+
       test('provides access to custom headers', async function (assert) {
         assert.expect(1);
         try {
@@ -348,6 +359,16 @@ module('OAuth2PasswordGrantAuthenticator', function (hooks) {
           assert.equal(error.responseText, 'The server has failed completely.');
         }
       });
+      test('rejects with response object containing responseText', async function (assert) {
+        assert.expect(1);
+        try {
+          await authenticator.authenticate('username', 'password');
+          assert.ok(false, "Test failed. Mustn't reach here.");
+        } catch (response) {
+          const text = await response.text();
+          assert.equal(text, 'The server has failed completely.');
+        }
+      });
 
       test('provides access to custom headers', async function (assert) {
         assert.expect(1);