My oil psi is reading 140 and I hear the engine tapping. It has enough oil. What can be da problem?

unless you are pulling a line trimmer and small engine --75psi is not enough to start anything
pouring in fuel floods the system so you need to pull it a lot with the plug out to remove the excess fuel

Don't know the specs for it, but it has to be over 100psi in each cylinder for the cylinder to fire and produce power. Less than that and it is questionable if the cylinder will even fire.
Do all of the cylinders. If the lowest reading is within 75% of the highest reading, then it is good.
Example- Nissan engine had highest reading of 160 psi, and lowest was 145 psi. That was a good engine with normal power. Another Datsun engine had highest 140 psi and lowest of 125 psi. Also a good running engine, but you could tell the power was just slightly reduced compared to a newer engine. Your VW should be somewhere in this range, the higher above, say, 140 or 150 psi, the better. If below 100psi, then probably internal mechanical problem.

You need to replace oil pump oil pressure should not be highyer then 60 psi

valve train noise is common in this line of engine and in no way will harm the engine, it is just a sticky cam follower

If you hear any knocking or ticking when the pressure is reading low, do not drive it 'till you have it diagnosed.
If the engine isn't noisy, you may have a pressure sending unit going bad. I'd definitely put a mechanical gauge on there just to read the actual pressure. If it is low, you may have some debris on the pump pickup screen that is obstructing oil flow Normally if it wasn't as low as yours is, I'd use an additive to dissolve the gunk but at 5psi you may do damage before the screen is clean enough so I'd recommend you remove the pan. If the mechanical gauge reads normal, replace the sender and don't bother with the remainder of what I am going to say.
If you remove the pan and find nothing on the screen, check the engine bearings for wear. If worn the correct way to repair that is to remove the engine as debris often will remain in the internal passageways and return to damage anything you put in there. Pump replacement is only necessary when you have bearing damage. Pumps do not generally fail unless they are contaminated. It will not hurt to replace one if the screen is obstructed as some debris can enter the pump and lower its pressure capacity somewhat but if the screen isn't blocked, do not blame the pump for the low pressure...you will be wasting your time and $ changing it.
Good luck...any further questions, just ask!

bout the oil pressure gauge its normal to go up but not to high coz u might overheat, try checking the cylinderhead gasket if there is pressure coming out, replace the gasket if needed

please befor you destroy the engine , have an oil pressure gage installed where your sending unit is to be sure you have enough oil pressure to even be driving the truck at all. on a hot motor at idle you should have at least 15 psi. at 2000 rpm you could have as much as 60 psi

That is probably a defective oil pressure gauge or a broken oil pressure sender, it reads 80 psi just because that is the maximum value allowed.

Pressure can be verified by reading it with a gauge tool.
If you really have pressure over 70 psi when engine is running then start replacing the oil filter, and check that the oil lines from pump are not obstructed, if there is nothing in there then replace oil pump.

If instead the gauge reads 80 with engine off, that is a defective pressure gauge.

I'VE GOT NEWS FOR YOU. AN OIL PRESSURE READING OF 140 IS EXTREMELY HIGH, LIKE OFF THE SCALE HIGH! THIS IS LIKE HAVING MOST OIL LINES PLUGGED WITH GOOP YOU HAVE BEEN DUMPING IN YOU POOR CAR TO TRY TO SOLVE THE PROBLEM. I REALLY HOPE YOUR OIL READING IN WAY WRONG, BECAUSE YOU ARE ABOUT TO BLOW THE RINGS AND MOST GASKETS AND MISC. PARTS OUT THE SIDE, TOP, AND BOTTOM OF YOUR ENGINE, FIRST OFF, I WOULD NOT DRIVE LIKE THIS UNTIL YOU DO THIS. PLEASE! DRAIN YOUR OIL AND GUNK, ALL OF IT AND CHANGE YOUR FILTER. THEN ADD A OIL LIKE STRAIGHT 30 WEIGHT OR 20-40W AND PLEASE HAVE A CYLINDER COMPRESSION TEST DONE ON YOUR VEHICLE TO SEE HOW BAD YOUR COMPRESSION LOSS IS. REMEMBER, STOP LEAK AND SUCH ALL PLUG YOUR HEATER CORE, SO DON'T EXPECT HEAT THIS WINTER. SORRY, NASTY SIDE EFFECT THEY DON'T BOTHER TO TELL YOU! GOOD LUCK! LET ME KNOW HOW THINGS TURN OUT! JUST REPLY TO: ARCLIGHT1217

Ckeck the ground wire located near the sensor... this causes this problem