During the Priority Mars mission, after your transport docks you are attacked by an increasingly more armoured enemy force.
I've shot my way through wave after wave of attackers, yet they never seem to end, then I run out of ammo and get my head handed to me.
Do the waves ever end or is this a case of progress or die?
I was able to pass the area by rushing the door but I'm concerned I may have bypassed an upgrade by not taking my time to explore.
I assume you mean the point when you arrive in the second cablecar. You'll have to fight quite some Cerberus troops there, but it does end after a while. There are no endless enemies at this point.
If you have ammo problems, powers like concussive shot are handy as they don't consume ammunition. And be sure to properly deal with shielded enemies and don't blindly emtpy your clip into their riot shield.
Use your powers, especially your group's powers, which are easy to forget about. Depending on your class/powers, take it slow and keep behind cover so you can kill all the easy targets with your powers before getting close or shooting off any bullets.
Use Liara's Singularity to take out shielded troops, don't waste your ammo on those otherwise. Enemies caught in the Singularity are great targets regardless of shields though as they take more damage per shot and thus less bullets to take down.
As a last resort, you could turn down the difficulty mode to Casual as well, enemies will drop a lot faster then. You can turn it back up after you finish the waves.
The waves will eventually end. If you're running out of ammo, try using more powers and advancing to overtake enemy positions and recover their ammunition mid-battle.
