Hey, I've never been in a S4 NA with WORKING secondaries so bear with me here. First off I found that the tube running to the left secondary actuator was off, so I hooked that up. Still didn't seem like anything happened, so I tried pushing in the valve. It was stuck, so I sprayed it down with penetrant oil and hammered it into submission. Now it moves up and down but its spring action is really weak and it usually just stays where I put it. The other valve is pretty stiff but it moves. How can I tell if these things are working? I don't really feel anything happen at/around 4000 rpm. Do you really feel them open or is it more subtle?

 

Do you still have the OEM exhaust on the car? If so, you're relying on backpressure to open the little guys up...

Easiest way to visually see if they've moved during a hard drive is to smother some bearing grease on the shafts and go for a drive- if they open, the grease will be displaced...

 

I only have the two cats and one of my mufflers off the Y pipe is missing I should be able to easily push them in with a finger right? And they should spring back to closed position afterwords?

 

No, not real easy to push them. With a muffler missing you probably don't have the back pressure necessary to open them in the first place. Plug the muffler-less Y-pipe end and take her for another spin, using the grease trick.

Note that if you have a source of compressed air, you can CAREFULLY ops check them with that (take the small line off of the split-air pipe nipple and blow some air in that end).

 

They should move with little effort and return to position on thier own.

Since you hammered on one, then either the actuator is sticking, or more likely the port tubes themselves are carboned up.

First you need to see if the entire actuating system is intact and tested per the FSM. If it is, and they still don't work, then it's time to pull the intake and decarbon the 5th and 6th ports.

 

welp i had a problem with hesitation at 4000 rpms due to the actuators, so i took them off and wired the ports open. The hesitation is gone and it runs awesome.

 

One way to feel if they are working is to go up a fairly steep hill in 2nd or 3rd. Hold engine at 3000 rpm then slowly crawl up to 4000 rpm, using about 1/2 throttle. Right about 3600-3800 rpm you will feel a somewhat dramatic torque loss, and you might hear a change in the tone of your intake/exhaust.
When your goin 1/2 throttle and they open up, you can feel it in the pedal that it's less responsive than it was just before they opened up (3400-3500), I believe 3500 rpm is where peak torque is.

 

Unless i have a problem with mine...but they seem to be working fine.