rockp2: you could also take the valve covers off and then start the engine and watch the valve train movement and for oil. However this method makes a pretty good mess as oil drips onto the exhaust manifolds and everywhere else....plus you still will not know what the actual oil pressure....just that there is or is not oil being pumped through the pushrods, but also lets you compare valve train operation between the cylinders.

I have done this in the past and found a rocker arm stud had come-out of the head; not on a 4.3 though.

Plus getting the valve covers off requires a bit of work, especially on the driver's side as the AC compressor mounting bracket usually requires being moved forward...and there is a hidden bolt accessible only from down-under; alternator must be moved as well. Guess you could leave the serpentine belt off for this test as long as the engine is not run for very long since the water pump will not be working.

Just offering an idea for you to think about.

 

Follow Lanny on this one. A bad gage is not going to make upper engine noise, no way no how.
Motor making low oil noise is not an instrumentation problem.

 

I'm not the OP

 

I had the same problem and it turned out to be blown head gasket, you might check your oil and water levels just to be safe

 

Thanks everyone for all your input It really is appreciated . I am waiting for a tester to arrive today. I will let you know how it goes.

 

sorry about that rockp2....no idea why I thought you were the OP....I think I posted very early one morning and was not awake.

Dustin Grant:....yes be sure to check the oil for coolant.