diff --git a/Lib/test/test_xml_etree.py b/Lib/test/test_xml_etree.py
index a7ad48b..3df1896 100644
--- a/Lib/test/test_xml_etree.py
+++ b/Lib/test/test_xml_etree.py
@@ -210,6 +210,26 @@
     """
     ET.XML("<?xml version='1.0' encoding='%s'?><xml />" % encoding)
 
+def processinginstruction():
+    r"""
+    Test ProcessingInstruction directly
+
+    >>> from xml.etree import ElementTree as ET
+
+    >>> ET.tostring(ET.ProcessingInstruction('test', 'instruction'))
+    '<?test instruction?>'
+    >>> ET.tostring(ET.PI('test', 'instruction'))
+    '<?test instruction?>'
+
+    Issue #2746
+
+    >>> ET.tostring(ET.PI('test', '<testing&>'))
+    '<?test <testing&>?>'
+    >>> ET.tostring(ET.PI('test', '<testing&>\xe3'), 'latin1')
+    b"<?xml version='1.0' encoding='latin1'?>\n<?test <testing&>\xe3?>"
+
+    """
+
 def check_issue6233():
     """
     >>> from xml.etree import ElementTree as ET
diff --git a/Lib/xml/etree/ElementTree.py b/Lib/xml/etree/ElementTree.py
index c47573e..2663b33 100644
--- a/Lib/xml/etree/ElementTree.py
+++ b/Lib/xml/etree/ElementTree.py
@@ -662,9 +662,9 @@
         # write XML to file
         tag = node.tag
         if tag is Comment:
-            file.write(b"<!-- " + _encode_cdata(node.text, encoding) + b" -->")
+            file.write(_encode("<!-- %s -->" % node.text, encoding))
         elif tag is ProcessingInstruction:
-            file.write(b"<?" + _encode_cdata(node.text, encoding) + b"?>")
+            file.write(_encode("<?%s?>" % node.text, encoding))
         else:
             items = list(node.items())
             xmlns_items = [] # new namespaces in this scope
diff --git a/Misc/ACKS b/Misc/ACKS
index b5dccde..847d1d1 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -529,6 +529,7 @@
 Sjoerd Mullender
 Sape Mullender
 Michael Muller
+Neil Muller
 R. David Murray
 Piotr Meyer
 John Nagle
diff --git a/Misc/NEWS b/Misc/NEWS
index 9d2b7cf..e544868 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -242,6 +242,11 @@
 Library
 -------
 
+- Issue #2746: Don't escape ampersands and angle brackets ("&", "<", ">")
+  in XML processing instructions and comments.  These raw characters are
+  allowed by the XML specification, and are necessary when outputting e.g.
+  PHP code in a processing instruction.  Patch by Neil Muller.
+
 - Issue #6233: ElementTree failed converting unicode characters to XML
   entities when they could't be represented in the requested output
   encoding.  Patch by Jerry Chen.