Sami951

Judging by the clues I've been picking up from here lately, I think I definately have a (vacuum/)boost leak somewhere...

Symptoms: very noticeable "swuiiiishhhh" spool up sound when you touch the gas pedal. Running super rich, black/grey smoke coming out when accelerating hard... also smells very much like unburned fuel on idle. I'm getting around 15l/100km (~16mpg if I got the conversion right). Doesn't really haul *** until revs get past 4000... slow to build boost - I get few psi before 3000, stock gauge pegs at around 3500.

The engine is otherwise stock, except for LBE and a set of chips (best guess at the moment is that they're Superchips or similar, haven't bothered to check).

So today I began ripping hoses out and so far I haven't found anything...

First thing was the intercooler pipes, the rubber pieces that hold them in place were all fine, no cracks anywhere... they felt good as well, not brittle or dried at all. The big-*** tube that comes out of the turbo was just as good.

Next up was the LBE, the hoses were good so I dismantled the thing (just in case) (man, it really is a simple device!) ... nothing weird in there either...

So now to the question: what other hoses I could easily check? I really hate the idea of removing the intake manifold and going through the mess underneath it, but I guess I could do it if there really isn't anything else left...

Also, where do the large hoses connected in intake manifold between the runners go?? I'm guessing the small ones deliver pressure signal to KLR (and somewhere else?)...

All suggestions gladly accepted!! Thanks!

oh yeah, looks like I'm losing coolant somewhere as well, aaaah crap....

Danno

How about that conical tube that goes from the intercooler-pipe onto the throttle-body? Also make sure the idle-bypass screw on top of your throttle body hasn't disappeared.

Another common source of leaks is the hose-octopus under the intake-manifold. The vacuum venturi-Y has an O-ring seal on the 180-degree bent hose that leads to the brake-booster. Also all those hoses aren't clamped down by real hose-clamps. When the hoses shrink with age, they open up a leak. If you can spin a hose on any of the metal tubes, the idle-stabilizer or the ventury-Y, then you should replace it and use a real hose-clamp.

Any one ever gotten a hole in their intercooler from rocks???

emilios

Sami,

my best friend has had this problem on his 944 turbo cab, and we just repaired it half an hour ago. I would suggest you remove the air filter cover, and check for all turbo/intercooler/air flow meter hoses and their corresponding clips holding them in place. Check them for tightness and whether they are correctly in place. My friend's car just came back from a service and almost everything was left loose...

Sami951

Took the conical ic-pipe <-> throttle body tube out as well and it was fine... I'm now putting (or at least trying to put) everything back. The intake manifold will have to wait

One funny thing I came across was a small hole in a bottom corner of the air filter box.. at first I thought that it shouldn't be there, but now I'm thinking it might actually serve as some sort of draining hole... anybody else have that?

Danno

That hole at the bottom of the airbox used to have a hose that connected to the belt-covers on the engine. You should plug it up with part# 944.106.103.00 and plug the hole in the belt-covers with #944.106.103.03.

Apparently, some people reported that the hole was sucking belt fragments and dust into the clean filtered section of the airbox.

Also inspect your rubber J-boot as well, those tend to crack right where it attaches to the turbo.

Sami951

Aww crap, I already put everything back in place... the j-boot will have to wait

Thanks for the tips so far!!

One more thing I noticed: the thing on AFM where you're supposed to be able to adjust (idle?) CO... looks like on mine there's just a hole and nothing you could turn in any direction. So I figured what the hell and just filled it with some silicone sealant... and (could be just my optimistic *** dyno though) it seemed to help just a tiny bit! Weird.

Mike S

This is what I did for mine.....

Take the airbox off or air filter depending on what you have. Plug a new fuel filter into the J-boot. Plug all remaining hoses on the J-boot with bolts and a zip tie. Then hook up an air source(air compressor) to one of the hoses....i have a gas station style tire inflator that works well. Pressurize the intake with 5-10psi of air. You can also plug the exhaust pipe, but my leak was so obvious I could hear it without doing that.