diff --git a/test/lisp/net/tramp-tests.el b/test/lisp/net/tramp-tests.el
index 50687dfe993..de343596969 100644
--- a/test/lisp/net/tramp-tests.el
+++ b/test/lisp/net/tramp-tests.el
@@ -7413,6 +7413,8 @@ tramp-test41-special-characters
   (skip-unless (not (tramp--test-rclone-p)))
   (skip-unless (not (or (eq system-type 'darwin) (tramp--test-macos-p))))

+  (tramp--test-instrument-test-case 10
+  (setq tramp-debug-to-file t)
   ;; Newlines, slashes and backslashes in file names are not
   ;; supported.  So we don't test.  And we don't test the tab
   ;; character on Windows or Cygwin, because the backslash is
@@ -7468,7 +7470,7 @@ tramp-test41-special-characters
     ;; Simplify test in order to speed up.
     (apply #'tramp--test-check-files
 	   (if (tramp--test-expensive-test-p)
-	       files (list (string-join files ""))))))
+	       files (list (string-join files "")))))))

 (tramp--test-deftest-with-stat tramp-test41-special-characters)