Noisier motor / innjector pump after some 4x4-ing

[gdb]

update.
issue was a cracked primer underneath and it was sucking air into the fuel lines causing erratic motor behavior. new primer and a few lines and she now has the good ol' 4.2 purrrr.. missed driving the old girl. thanks again folks. nissannewby was on the money when he mentioned "air ingress". owe you a beer or 5 mate.
cheer. garry.