Engine cranks but does not start

Hard to say, there are many times where someone finds the problem but never returns with any updates. It is one of the problems with sites like this, cliffhangers abound.
Do you have a similar problem?

Okay, what testing have you done to it if any? That behavior could be many things from an intermittent fuel pump relay to a bad connection at the ignition module. Could you give any more information as to any common things that happen when it refuses to start? Like it does it after it sets for a day, or it does it when it's driven hard? That way we can start with a clean slate.

So, it will crank over good but doesn't start, how long do you need to wait until it starts?

Just to jump in on this because I saw your other thread on this, and I had some ideas but don't want to take over from Steve W.

Since this is so intermittent it is going to be hard to test until it starts doing it more but when this is cranking but not starting it would be helpful to know what the fuel pressure is. Here is a guide that will help with testing this:

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

However, what I am suspecting because I have seen other Frontiers with fuel pump issues that at times, it does not build enough pressure to start the engine. Then after a minute or two you cycle the key, and it builds the pressure.

So, the thought on this is that it is not the waiting but the cycling of the key that gets the engine to start.

So, one way to test this is the next time it acts up and cranks but does not start. Turn the key completely off and then to the on position and wait 3 seconds. Then do it again. Then try to start.

What you are doing is priming the fuel system and if it fails to start the first time but then you cycle the key and prime it again and it starts then the pump is starting to fail.

Otherwise, you are going to have to tape the fuel pressure gauge to the windshield and wait for this to happen again to see what the pressure is when it acts up.

Jump in anytime. That was why I asked about the time, was thinking the same thing. Either not priming or the relay is sticking. The test above should help. The pump relay activates for three seconds at initial key on and then once it sees a crankshaft signal showing the engine is running at above a set speed it turns the relay on and keeps the engine running.
The description sounds like it is losing pressure rapidly.

That is one of the problems with intermittent faults, waiting until they happen. I would still do the pressure tests, that would give you an idea of the pumps condition at least. Let us know what happens please.
Cannot think of anything that would make it spin faster, compression isn't going to go away like that. It could be a high draw from the fuel pump but I wouldn't think you would see any cranking difference unless it's a bad ground from the battery to the chassis causing it. However if that was the case I would expect to see other issues like dim lighting or other obvious clues.