Purging air every 17 seconds.

my truck had the same problem it was the air line from the governor to the dryer. use a spray bottle with soapy water in it .check it with truck running or you won't find it. mine was hard to find it would blow the soap away from the leak before it would bubble .

 

I had that on a truck, was the 'push-to-connect' plastic fitting on the governor sensor line.

 

that's what mine was. cut the end off and put a new connector on.

 

The dryer may just be getting bad. sometimes you've got to put a new dryer on just chanson filter isn't enough

 

It is not the dryer, it can not cycle itself,
Plastic line from governer to air tank is leaking, look for a place it can rub.

There is a check valve at the tank so it won't leak when shut off, only when compressor is adding air.

 

the leak was about 6" from the gov. in at a coupler. I got a new coupler an cut off the line just enough to have a smooth place for the new coupler.