quick question(please respond ASAP cause I wanna go to lowes)

I always have problems boost testing my car. Has anyone ever used like an electric compressor? Mine puts out a constant psi, but isn't adjustable, so it doesn't seem like it's putting in enough air to pressurize the system. The most I can ever my boost guage to hold is 1psi. I've tried a bike pump too, but I think you run into the same problem not being able to compress enough air into your system.

Is it possible that I have a leak bad enough to allow it to hold only 1 psi, or should I run out to lowes and pick up a tank that'll flow, say, a constant 20 psi? I've done the vaccum line elimination thing, resurfaced my throttle plate elbow where the UICP bolts to the manifold(with gasket of course), I've just replaced all my injectors with all new O rings and seals, and a new gasket going from my LICP to my stock IC. Now could there possibly be a leak that big anywhere?! Or do I need a better compressor.

It could be a leak that big. Did you hear any hissing once you stopped compressing the air? If not, then the leak may be so big that its getting out of the system before you even have time to stop compressing it... Also, do you have any problem building boost when you drive it?

It could be a leak that big. Did you hear any hissing once you stopped compressing the air? If not, then the leak may be so big that its getting out of the system before you even have time to stop compressing it... Also, do you have any problem building boost when you drive it?

Nope, no problems, I'm pushing a steady 18 pounds and holding. I just don't understand what could be causing it to hold no pressure.

When i leak tested mine i used a air tank and it worked fine. To make sure i did not have any small leaks i used a spray bottle of soapy water, but that does not sound like your problem. Your problem sounds big. GL man

You are right in thinking that you need a large volume of air available to build pressure in the intake system. A bike pump and small electric tire pumps are not going to work. At the minimum use one of the small tanks that can be filled at a gas station's air compressor for example. That can provide enough air volume and pressure to do a meaningfull test. Big leaks are tough to find though since the tank is still relatively small and can run out quick. Even with my 30 gallon compressor I have had leaks big enough to empty it before I found the problem. I eventually made a tester that has a air hose quick disconnect on it rather than a tire valve, since the tire valve was much smaller than some of the leaks I have had ;) But you get the idea. Good luck.

You are right in thinking that you need a large volume of air available to build pressure in the intake system. A bike pump and small electric tire pumps are not going to work. At the minimum use one of the small tanks that can be filled at a gas station's air compressor for example. That can provide enough air volume and pressure to do a meaningfull test. Big leaks are tough to find though since the tank is still relatively small and can run out quick. Even with my 30 gallon compressor I have had leaks big enough to empty it before I found the problem. I eventually made a tester that has a air hose quick disconnect on it rather than a tire valve, since the tire valve was much smaller than some of the leaks I have had ;) But you get the idea. Good luck.

How is it then that people have used bike pumps and claim it works? And if I get an air tank to test it, does it have to be the type with a regulator, so I can push a constant psi? Or will any air tank work?

I have no idea how people get a good test with a bike pump, unless they don't have a massive FMIC with large IC piping to fill and there are no leaks to find ;) It's also important that the pump/tank/whatever be silent so you can hear leaks. You don't need a regulator if you "regulate" it yourself. It takes time to move air through a shraeder valve, so just watch the guage and let off at the appropriate time. If you use a quick disconnect like I mentioned for high flow rates, then you would need a regulator.