Nissan Patrol 2002 ZD30 Intercooler Problems

Our ZD30 engine bleep itself a few months ago and I was able to find a second hand replacement engine however we now have realised the intercooler is buggered. We had the intercooler tested and it holds no pressure what so ever.

Our Question: If the intercooler was not working at all and held no pressure what affect would this have on the engine especially on a long trip.

The motor blew while driving from Coffs Harbour to Sydney. We were approx 60klms from Sydney when the motor let go. (what a mess)

We are asking this question as we are wondering if this issue had something to do with out motor going Kaaboom. The number 3 conrod snapped just at the base of the piston and we suspect the motor may have got way too hot and resulted in the conrod letting go.

Note: There was no prior warning to the motor go off with no sensor lights appearing on the dash or any other malfunction lights showing up. The temp control on the dash was within the normal range.

Any info will be appreciated.