This article will serve as a hub for all Porter Cable air compressor not building pressure, related issues. It’s a very common problem for Porter Cable air compressor will not build pressure, and so, this article will present the reasons why this occurs, along with current reader questions and answers.
Table of Contents
- Reasons Porter Cable Air Compressor Won’t Build Pressure
- Reader Questions and Responses – Porter Cable Compressor Won’t Build Pressure
- Additional Porter Cable Pages
Reasons Porter Cable Air Compressor Won’t Build Pressure
The most likely reasons why your Porter Cable air compressor won’t build pressure are summarized in the table below along with clues.
Reason | Clue |
---|---|
Failing Intake Valve | The compressor will draw air in on one cycle, but then that air will blow right back out the intake valve. |
Failing Pump Pressure Valve | Air will flow into the tank through the pressure valve on the compression stroke but then be drawn right back out of the tank as the piston cycle to try and draw more air in through the intake valve. |
Gasket Failure | The compressor may be working fine, but as it is cycling, the air is flowing back and forth across a failed gasket inside the pump instead of being forced into the tank. |
Piston Seal Failure | The pumps will lose pressure and compression strength. This can also reduce the pump’s efficiency to optimize the production of compressed air. |
Compromised Tank Check Valve | The discharge head of the pump will receive a high pressure of air. It will affect the pump’s motor might and stop it from restarting anytime the tank is full. |
Please visit our Why An Air Compressor Won’t Build Pressure & How To Fix A Compressor Not Building Pressure guide for detailed information on each, along with how to conduct the necessary checks! If you’re wondering why your air compressor won’t stop running, we also have a guide on this!
Reader Questions and Responses – Porter Cable Compressor Won’t Build Pressure
CPF6025VP Porter Cable Air Compressor Not Building Pressure – Porter Cable Air Compressor Troubleshooting
Question
It starts and runs, but sounds a lot quieter than it did, only pumps to 20psi, and shuts off. It also sounds funny. Like an echo, hollow-type sound. My first thought, of course, was the pressure switch, that shuts it off was bad, but the running quiet, and sounding funny throws me off. Any ideas are greatly appreciated.

Response
Mark, there are a number of reasons why an air compressor will not build pressure, and why an air compressor will shut off before the tank pressure reaches the normal cut out.
The sound change suggests to me a valve and/or gasket problem.
But, the compressor should not shut off at 20 PSI, even if that’s all the pressure the pump can generate, unless, of course, it’s running so long it overheats and goes off on the compressor tripping thermal overload.
If the compressor shuts off at 20 PSI and the pump and motor are fairly cool, as in only running a few minutes, you need to have a look at the pressure switch innards to see if the pressure switch has tripped off. If it has tripped off at 20 PSI, then I would suspect the switch itself is the issue.
Other reasons why a compressor will not build pressure are covered on pages linked from the troubleshooting page. Help yourself and please tell us what you found.
Model 2002 Porter Cable Air Compressor Won’t Build Pressure – Porter Cable Air Compressor Common Problems
Question
Bought it 4 years ago, and used it maybe 6-8 times. Not enough to say I’m familiar with it.
(1) I know oil less is not a ‘real’ compressor, but it suited my space and use requirements when I bought it.
I’m trying to figure out exactly how it is supposed to work.

I thought I knew, but it isn’t working that way.
(2) I believe you plug the compressor in, turn it on and let it run up to whatever pressure. (It is supposed to be 150 PSI, I don’t think I’ve ever had it over 100 though).
So I run it to 100, set the regulator to 70 (which is what I need for the air eraser I’m using), and turn it back on.
(3) I thought I remembered that you leave it on, and when the pressure in the tank drops below 70, the compressor would kick on and bring it back up to 70.
Not happening. It just keeps running constantly, whether the tank pressure is higher or lower than the regulator pressure. The only way to shut it off is to manually shut off the power button. Air Compressor not shutting off.
Do I have a faulty regulator or???
Any help is greatly appreciated, thanks!
Response
Herb, I added some numbers to your text rather than retyping all of what you entered, and the answers to the numbered questions are below.
(1) Oil-less air compressors are very much real compressors.
(2) Yes, this is how they are supposed to work.
(3) No. That’s not it.
The specs for your compressor are:
Cut-Out Max: 150 psi
Tank Size: 6 gal
Cut-In Restart: 120 psi
Air Delivery @ 40 PSI ISO1217: 3.5 SCFM
Air Delivery @ 90 PSI ISO1217: 2.6 SCFM
If you’re wondering what SCFM is, visit our SCFM vs CFM guide for more information!
Your air compressor should turn on, should run up to 150 PSI in the tank, and should turn back on when the tank pressure drops to 120 PSI, regardless of what you have dialed in on your regulator.
See the regulator page on this site for a better understanding of what they do.
If your air compressor only gets to 100 PSI in the tank when you are not using air and keeps running, your compressor is sick. See the troubleshooting page about air compressors that run but don’t build pressure for some tips and things to check.
If you are using air while the compressor is running and your air pressure doesn’t rise to the normal cut out, you are using more air than the compressor can deliver. See the delivery specs above and check to see if they are greater or lesser than the air demand of your air eraser.
6 Gallon Porter Cable Air Compressor Won’t Build Pressure – Porter Cable Air Compressor Troubleshooting
Question
I have a 6 gal, the tank pressure builds up and the outlet gauge shows up to shut off, but when I use air it hardly lets out any and then sometimes builds up air slowly or not at all.
Can not seem to find an online parts manual so can’t get the part if it is the regulator.
Can you help?
Dwaine
Response
Hello Dwaine. Please see his page about no air out of the hose. There are some things there you can check.
When you have done so, add a comment here with your findings, if you wish, particularly if you haven’t solved the compressor problem.
Porter Cable Will Not Build Pressure – Porter Cable Air Compressor Troubleshooting
Question
Bill,
I have a Porter Cable 25 Gal upright 135 PSI Model # CPF 6025UP.
The motor runs great, pulling air through the inlet but no pressure at all. Checked all plumbing no leaks. I really can’t figure this one out. Any ideas?
Response
Hello Joe.
You’ve ruled out the valve issue by checking that the intake port is actually drawing in air and not blowing it back out. That suggests that the valve is fine.
Do the same for the line that goes to the tank from the pump head, and be sure that air is being pumped out strongly. Try to stop it with a gloved finger. You shouldn’t be able to.
If there are no leaks, all other things being good on your air compressor as they seem to be, my guess would be a gasket failure under pressure inside the pump.
Cheers,
Bill
Additional Porter Cable Pages
- Porter Cable Air Compressor Won’t Shut Off
- Porter Cable Air Compressor Keeps Tripping Breaker
- Porter Cable Air Compressor Leaks Air
- Porter Cable Air Compressor Oil – Choosing Oil, How Much To Use & Changing Oil
If you have any questions about Porter Cable air compressor not building pressure, please leave a comment below, with a photo if applicable, so that someone can help you!