The sensor is located in {HEAD ~ an engine component opening}, such as {TAIL ~ a spark plug} well, and is engaged with first and second walls that define the ends of the opening 
The sensor is located in { HEAD ~ an engine component opening } , such as { TAIL ~ a spark plug } well , and is engaged with first and second walls that define the ends of the opening
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH