diff --git a/src/octoprint/util/comm_acc.py b/src/octoprint/util/comm_acc.py
index 16301222..65b34fc5 100644
--- a/src/octoprint/util/comm_acc.py
+++ b/src/octoprint/util/comm_acc.py
@@ -1732,7 +1732,8 @@ class MachineCom(object):
 
 		try:
 			if "?" in command:
-				self._log("--- found ?: ", command)
+				string = "--- found ?: %s" % command
+				self._log(string)
 				if self._status_report_queued is True:
 					return
 				else: