Help please - Air compressor starts with low pressure

[diggerwolf]

My old, inherited air compressor finally gave up the ghost. Using my backup now. However, it exhibits a weird problem when I use it.

Although it seems to fill, no leaks, and holds pressure, when I first start using it, whether a blow gun or air chuck, the pressure is incredible low at first, then builds up.

What would cause this, and how do I fix it?

Thanks!

 

[GATORB8]

Tank pressure is low or output pressure is low?

 

[diggerwolf]

Output pressure. I don't have a way to measure, but I guess 20 psi or something, then builds up to full pressure. This is while I depress the blow gun, or air a tire. Low at first, then builds up to a usable flow.

 

[GATORB8]

Sounds like it could be a bad regulator? Especially if your pressure is good at the tank gauge.