diff --git a/tests/test_engine.py b/tests/test_engine.py
index 2558b8dc6..4bfccdb18 100644
--- a/tests/test_engine.py
+++ b/tests/test_engine.py
@@ -26,7 +26,6 @@ from scrapy.exceptions import CloseSpider, IgnoreRequest
 from scrapy.http import Request, Response
 from scrapy.item import Field, Item
 from scrapy.linkextractors import LinkExtractor
-from scrapy.signals import request_scheduled
 from scrapy.spiders import Spider
 from scrapy.utils.defer import (
     _schedule_coro,
@@ -621,7 +620,7 @@ def test_request_scheduled_signal(caplog):
 
     engine._start = start()
     engine._slot = _Slot(False, Mock(), scheduler)
-    crawler.signals.connect(signal_handler, request_scheduled)
+    crawler.signals.connect(signal_handler, signals.request_scheduled)
     keep_request = Request("https://keep.example")
     engine._schedule_request(keep_request)
     drop_request = Request("https://drop.example")
@@ -630,7 +629,7 @@ def test_request_scheduled_signal(caplog):
     assert scheduler.enqueued == [keep_request], (
         f"{scheduler.enqueued!r} != [{keep_request!r}]"
     )
-    crawler.signals.disconnect(signal_handler, request_scheduled)
+    crawler.signals.disconnect(signal_handler, signals.request_scheduled)
 
 
 class TestEngineCloseSpider:
@@ -646,9 +645,13 @@ class TestEngineCloseSpider:
     async def test_no_slot(self, crawler: Crawler) -> None:
         engine = ExecutionEngine(crawler, lambda _: None)
         await engine.open_spider_async()
+        slot = engine._slot
         engine._slot = None
         with pytest.raises(RuntimeError, match="Engine slot not assigned"):
             await engine.close_spider_async()
+        # close it correctly
+        engine._slot = slot
+        await engine.close_spider_async()
 
     @deferred_f_from_coro_f
     async def test_no_spider(self, crawler: Crawler) -> None:
@@ -704,9 +707,16 @@ class TestEngineCloseSpider:
     ) -> None:
         engine = ExecutionEngine(crawler, lambda _: None)
         await engine.open_spider_async()
+        signal_manager = engine.signals
         del engine.signals
         await engine.close_spider_async()
         assert "Error while sending spider_close signal" in caplog.text
+        # send the spider_closed signal to close various components
+        await signal_manager.send_catch_log_async(
+            signal=signals.spider_closed,
+            spider=engine.spider,
+            reason="cancelled",
+        )
 
     @deferred_f_from_coro_f
     async def test_exception_stats(