Vacuum sucks!

2.5InchTrueDual · #1 02-16-2009, 12:01 PM

My SVX hase been running rough lately so i went looking of vacuum leaks. i've found my vacuum leak and i think i now have to take my intake off. I was looking at all the hardlines that run behind that alternater and power steering pump on the front end of the engine and noticed a small rubber hose connected to that intake that ran under the intake, to a valve, then into a black box under the intake. Most of my other rubber lines are still in great shape, this one was as brittle and took no pressure to snap off at the valve. it also broke as i was trying to get it of the nipple on the intake and it broke the nipple off the black box under the manifold. Anywho let me know if you recognise that black box that i'm talking about. I'm including 2 pics. one is of the hose and valve and the other is where the nipple broke off the box and the brass nipple on the manifold(still has a chunk of hose on it). Let me know whats up and what i have to do to fix it.

liamrh · #2 02-16-2009, 12:44 PM

Iris valve?

2.5InchTrueDual · #3 02-16-2009, 12:55 PM

Thats what I was thinking. Is that the black box or that broken valve. that valve is a non issue i was wondering exactly that the bax is and that do i have to do to get it out? I have a parts car but i know that same thing is going to happen when i go to take it off the parts car.

Manarius · #4 02-16-2009, 02:27 PM

The little thing in the second picture is the IRIS check valve. Definitely something worth replacing. The black box I would guess is the IRIS itself since it's so close to the IRIS check valve.

Blacky · #5 02-16-2009, 03:39 PM

I broke a mystery hose also on Saturday while trying to change the @#$&*
PCV valve (unsuccessful). It was like petrified rubber or porcelain. It comes off the throttle body and goes under through the opening for the PCV valve. It broke a plastic nipple off of something under the manifold but I can't see what. I put a screw in the vacuum end (throttle body end) to block it and the car runs fine. I'm definately not taking the manifold off unless something critical happens.
One good thing came of it though. I found the dipstick had popped off the front differential and 2/3 of the fluid had blown out of it. The car smoked sometimes, now I know why.

IceBlade · #6 02-16-2009, 07:41 PM

How would I go about checking my vacuum hoses to see if all is well?

2.5InchTrueDual · #7 02-16-2009, 11:36 PM

A big ol' can of starter fluid does the trick. Spray it on any vacuum line or anywhere you think its leaking and if your RPMs bounce up alittle and goes back to idle then you know you have a leak. What does IRIS stand for and what does it do? I dont want to bypass it cuz i know if its there it has to be doing something, right?

longassname · #8 02-17-2009, 02:06 AM

the "black box" under the intake is a vacuum canister. If you broke it..... replace it. Get your new dealer parts while you still can. It won't be long before they aren't available anymore.

on a side note..

not as a disparaging comment or anything as I've done it myself--the upper intake isn't meant to be removed from the lower intake stacks on the car. If you take the whole intake, both upper and lower along with the fuel and vacuum lines off of the engine as a unit these parts don't get broken.

2.5InchTrueDual · #9 02-17-2009, 09:42 AM

Thanks for the help. I "really" cant wate to do this repair as it will be the first time taking the intake off. Has anyone managed to get that vacuum canister out without taking off the intakes? Anyone With any advice? Taking it to a shop isn't in the cards as i like to do all the work on my cars, plus that and its a helluva ot cheeper to just do it yourself. I'm thinking i might buy a few feet worth of new vacuum hose in assorted diameters cuz if one line breaks most of the others have the posibility. If I take the manifold off is there anything i might want to take care of while i'm there, new fuel pressure regulator, O-rings round the injectors? I think i once read a thread of people using a legacy Fuel pressure regulator, what would be the benefit in using a Lagacy FPR? Little more pressure on the fuel rail? I'm also taking to mind that need for gaskets. Can anyone who has done this repair give me a quick run down on this sometime? Parts, special tools involved, tips, tricks, and secret methods to these quarky cars are sometimes the best thing to know! Thanks
Will

longassname · #10 02-17-2009, 02:12 PM

the intake manifold actually comes off pretty quickly and easily if you do it right. If you try to remove the upper intake and leave the injector stacks on the engine it's a mess and stuff will likely break. If you unbolt the injector stacks from the engine the whole intake assembly comes off of the engine in one piece complete with fuel lines, vacuum lines, harness, and all.

If you go look towards the end of the thread on my engine build you'll find some pretty good pictures.

Blacky · #11 02-17-2009, 03:26 PM

Knock sensors and PCV are a lot easier with the intake off.