Lethal time to have to pull up (4)
I believe the answer is:
halt
'pull up' is the definition.
(I've seen this before)
'lethal time to have' is the wordplay.
'to have' indicates the answer is hidden within the clue.
'HALT' can be found hidden inside 'lethal time'.
'to' is the link.
(Other definitions for halt that I've seen before include "Stop, small station" , "limping" , "Stop or pause" , "Bring to a stop; lame" , "game" .)