Pressure guage is at 0 with pump on but big pump (sorry first timers here, no pool expeirience) doesn't seem to be working and no vaccum suction.

The same thing happened to me. So frustrating! I guess the pump that comes with the intex pool is not strong enough to do this. At least that is what I was told. So I just ended up sending that vaccum back and getting a catfish vaccum. Works great!

if you are sure water is circulating (check to see if water is being sucked into the skimmer suction port or you can open your air relief valve on top of your filter and water squirts out,) then you will know that all works, but if pressure gauge is "0", then replace your pressure gauge.

Does it show pressure when in "Filter" mode?

If not, then your pump is either not primed, Impeller is plugged, or there is not enough water in the pool, you are sucking air.

Probably need new pump if the impeller broke.
If impeller broke, then motor will run, but no water circulates
Call pool company.
Motor resources:
http://waterheatertimer.org/Color-codewire.html#motor

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

suction leak, cracked lid or a leaking valve in the suction line

check the impeller for debris. you will have to take the metal band off that connects the wet end to the seal plate. inspect the impeller for debris. lube all o-rings and reassemble. if that does not work, investigate a blockage in the suction side plumbing.

turn the pump off, remove the lid and pump basket. reach your finger inside to see if there is any debris caught in the impeller. MAKE SURE the pump cannot come on at any point while you're working on it.
That should do the trick, if not, investigate an air leak on the suction side of the pump. Causes: bad lid 0-ring, threads on suction fitting leaking air in, or if there is a union on the suction side, make sure it's tight and the o-ring is in good condition (add lube as necessary).

I think you meant that the pump keeps filling with air. You may have an air leak on the suction side of the pump. If you turn the pump off, you should not see any water leaking out of anywhere, if you see any water drip near the suction side of the pump, you should consider that an air leak and repair it.

The problem you're having seems to be an air leak. when you connect the manual vacuum or if the system is running normally, there is not nearly as much suction that is created as when the zodiac is plugged in. The air is forcefully pulled into the system when increased suction is created.

Try replacing the lid o-ring and investigate any possible places on the suction side of the pump that could be a potential leak.

Hope this helps.

it sounds like you may have a suction side leak on the pump. check the lid o-ring and the suction side fittings to see if there may be a possibility of air being sucked into the pump and causing it to act like it's picking up prime and then losing it.

First of all fill the pool up. Then wrap a rag around a hose and force water into the suction line. If you have problems still, you may need to replumb the pump or change the seals.