One other alternative is that the sand in the filter has become "channeled", that is, the water has worked open "holes" in the sand and is streaming right through (without really going through the sand).
Try a good backflushing, that usually fixes the channeling, if that is the problem.
If still zero pressure, then try replacing the gauge.
Hope this helps...
I think your gauge is defective. Filter channeling will provide poor water filtration. Backwashing should be part of regular pool maintenance. Check pressure after backwashing. When the pressure rises 5 or 10 pounds it is time to backwash again. Keep in mind that as the pressure increases the filter becomes more effective at removing particles but also allows less water to be filtered. Never allow the pressure to exceed the manufacturers maximum pressure rating for the filter. Get a new gauge. They cost a lot less to replace than a burst filter.
The gas is probably not leaking into the filter but the engine. It's caused by a broken diaphragm on the fuel pressure regulator. Replace regulator
Probably because it is clean, leave it on the filter setting for a while and you will find that the pressure will increase as the filter gets dirtier, when it get high (usually in the red ) you will have to backwash.
I think when it happens when the pool starts to turn green
If one bank is running lean it usually means that you have a vacuum leak somewhere on that side. Check for broken hoses that connect to that side or possibly broken gaskets. changed all hoses what gasket
Probably not , but check the owner's manual, it should list it, if it's there.
it will be at the oil filter probably a 3 wire plug if not on the filter boss beside under or over it but very near filter
Fuel filter, fuel pump, or pressure bypass/relief valve is not providing the correct, enough fuel pressure at the injectors.
sounds like a fuel problem check first for a plugged fuel filter if filter is OK, it is likely a fuel pump, if you have access to a fuel pressure gauge check fuel pressure a test port is located on the back of the manifold on the drivers side should be around 60lbs of pressure if not you probably need a fuel pump. the other alternative if filter is good and fuel pressure is good it may be a plugged catalytic converter
The lower the better some run around 9 psi with new filter media, as the filter media gets old the filter has to work harder so the pressure will go up in the filter, so what you need to do to see if you filter is running ok, is to simply take your hand and place it in front of a inlet in the pool if it pushes your hand away you have good pressure take a reading at the filter and see what you have. If it does not push you hand away you will have high pressure at the filter and filter media may need changing or the filter may need backwashing, we have people who refuse to put a new pressure gauge on their filters they say they cost too much, and that's how they check their pressure.
bad gas filter block or low fuel pressure
Sounds like you may have low fuel pressure. When did you last change your fuel filter? JA