Street King

OK part 2 of the boost problem. I think I got it down to the CRV is what's wrong. I try that Aux. to On and back and forth with the key and I don't see it moving or having any vacuum. AS of right now the best way to explain it is a 8-4-8 boost pattern that feels like its running Non-Seq. mode but it's not. Boost builds slow and the switch to secondary turbo dips to much leading me to believe the secondary turbo is not-pre spooling. One thing that I have found is that the CRV is very loosly held on by the clamp. I could turn the hose 180 degree with my pinky finger. Feels like I can take it off with my fingers. You guys think this might be the problem?

zayrx7

check your bov

Street King

I have it vented to the atmosphere and it does blow off when I left off the pedel(while on boost). How do I check to makesure its properly working?

P'cola FD

It is possible that the hose going from the y-pipe to the CRV is leaking boost. If it is that loose I would replace it.

rpm_pwr

Hey street king,

I apreciate you're having a bit of trouble making sense of all these acronyms but I'll keep trying:

You're confusing the CRV and the Charge control:

Charge control:
Is mounted on the y-pipe itself, slightly offset to the secondary side. It allows pressurized air from the 2nd turbo to flow into the y-pipe, thus giving you secondary boost. When you turn the key the charge control actuator pulls the rod in which closes the flapper door. This BLOCKS OFF the 2nd turbo.

Charge releif Valve(CRV):
This is basically a BOV being used for something else. The vacuum hose is controlled by a solenoid in the rack. The pressure side is connected to the 2nd turbo outlet. Under 4500rpm this valve is OPEN allowing prespool boost of the secondary to vent into the airbox. Above 4500rpm the VALVE is CLOSED forcing all the air into the y-pipe.

To learn more and see where these parts are look up the service manual:
http://www.iluvmyrx7.com/3rdgen/manuals/93%20manual/(F)fuel_and_emissions_control_systems.pdf

Now we've cleaned that up:
The key-off ken on trick powers up the CRV and Charge control solenoids. So when the the key is off, the CRV is CLOSED (you cant blow through it) and the charge control is OPEN (the rod is OUT) Switching the key to on puts vacuum on both these valves. This pulls the CRV OPEN (you can now blow through it) and the closes the charge control (the rod moves in)

Sooooo:
* Put key in ACC
* Pull CRV off the air box
* try to blow through the CRV (you cant)
* look directly at the charge control actuator ROD
* get someone to turn the key to ON
* You should see the actuator rod move into the actuator
* now try and blow through the CRV you SHOULD be able to now.

If cant do either or both of the last 2 then you vacuum system is fucked. Try pulling the vacuum hose (small hose) off the CRV when the car is OFF. You should here air suddenly rush in If you dont you have a vacuum storage/switching problem (I'll talk you through that too)

BTW dont worry about the lump idle without the air pump - its normal.

-pete

rpm_pwr

oh yeah and fix your damn pipe!

-pete

Street King

OK I can't do that right now since I'am at work. Will do it tonight since you greatfuly cleared that up for me.I have the service manuel, I was just looking in the wrong section(engine). Thanx for the help so far and I'll get back to ya, and what pipe is it that you want me to fix!

Street King

Yeah I have all the tools for the NON-SEQ. and a person willing to take the time out to help me do it. Will go non-seq sooner or later. Kinda wanna get a few more mods before going non-seq. Just want to get this boost problem over with ARG!

rpm_pwr

some of us enjoy full boost at 2000rpm And with NON-SEQ you lose a LOT of bottom end in 1st and 2nd. I'll admit it's not as bad in 3,4 or 5 but I think it's a step for the worse on a daily driver.

-pete

rpm_pwr

BTW the pipe to fix is the loose one! (CRV pressure side) You could probably just get away with using a worm gear hose clamp.

-pete