special tool

Dude..... oil??? No
Cycle valve takes positive pressure from banjo and routes it either to the wastegate (when klr wants it open) or to the intake (when klr decides to give up some friggin boost). When cycle valve breaks, or when there is an error, it always goes to the wastegate - which OPENS the wastegate (NO boost)

This runs contrary to any REAL wastegate in the world like Tial, delta, hks, etc. Porsche is backwards - big surprise.

Porsche-O-Phile

Sorry, I misunderstood. On some of the literature / write-ups I've for the turbocharger replacement I just did, it kept referring to a large bolt (referred to as the "banjo bolt") that appeared in the diagrams to be below the turbocharger, and to carry oil. As such, I thought this term (banjo bolt) referred to the big sucker that returns to the pan. I'm assuming that the "correct" use of the term "banjo bolt" referrs to the vaccum line on the hot side intercooler pipe that connects via the venturi to the cycling valve.

I also got the piece of the cycling valve that had come loose siliconed back in place with the high-temp (copper) silicone. Apparently the P.O. had just trimmed a piece of circular plastic (looks like a type of vaccum hose to be honest) and jammed it in the "hole" on the side of the valve; maybe he had busted it off previously and that was his way of fixing it - dunno. Anyway, it looks like it's holding. I checked most of the other things you mentioned - it appears the problem is likely a stuck wastegate. I gave it a few firm taps with a hammer on the bolt heads to help "unstick" it (assuming that's a problem), although I've yet to do the formal "test" with whether the pipe gets hot or not.

It appears that all lines are accounted for and I spent some time taping / siliconing any connections that looked potentially like they could leak. I guess I'll know when I try to start it, but I'm suspecting strongly the wastegate is the culprit.

hosrom_951

Relief yourself from the CV and get a straight pipe with a MBC (Lindsey or Accuboost) connecting directly from the IC banjo to the WG........

Porsche-O-Phile

I might do that - I've heard good things about that setup. For now though, I just want the car to work correctly stock. I'm still a relatively "new" owner to this car and I'm still in the "undo all the damage done by the moron P.O." stage. After I get done with that, I'll be ready to start tinkering, although a lot of the Lindsey stuff has gotten excellent reviews. I just got done looking at their wastegates, should I end up needing one. . .

Eyal 951

Jeff,
LOL, you have lots to learn, and everyone is confusing you...
Give me a call tomorrow (past 5:15) and I'll answer all your questions and such. a WG wont be 1000, and 300 for a cycling vavle? friend, all you have to do is pay 60 for an accuboost, buy some vacuum line and go straight to the WG, thats how I am setup... anywho, gimme a call we'll talk.
~Eyal

hosrom_951

Eyal: Didn't hear from you in such a while how's that muffler coming along with you

Eyal 951

muffler wont be mounted for a bit more, i need to get my head back, get the car all together and such...
I went to the track (streets of willow) on friday and then straight up to northern california for the weekend.
~Eyal

Porsche-O-Phile

Cool - thanks man. . . Your 951 kung fu is stronger than mine.

I'm kind of learning as I go, but it sounds like there are other options. At least the car works for now, albeit boost-less.

Porsche-O-Phile

Just took it out for a spin - I'm getting 1.2 bar max. The seal-up job on the line from cycle valve to wastegate looks fine (I checked it all the way around with a small mirror - it looks like it's sealed up properly). I wonder if the position of the "banjo bolt" (the one off the intercooler hot / pressure pipe) matters - it appears this functions as the supply of pressurized air for the system, so if the bolt's "O" part was oriented so as to not fully line up with the hole in the hollow bolt that runs through it, perhaps the pressure value is not what it should be. I will ponder this for tomorrow.

UK952

Hi,
The divertor valve (recirculating BOV) has a small pipe on top that works a diagphram (which often fails) underneath it has a sprung piston that should open when the vacuum sucks on the small pipe, otherwise it should be closed. On my car when the turbo failed I played with it a bit (pushing the valve against the spring pressure and it got stuck sideways and open. This would allow the boost to go straight back into the intake rather than into the engine. Mine was also full of metal particles which was why I was opening it - i binned it and got a new (upgraded) one as i couldn't get them out.

The cycling valve can be bypassed with a reliaboost or boost enhancer and some rubber hose, so do not worry too much about fixing it. (But be careull not to run more than standard boost without chips and FPR).

Set up correctly the cycling valve can only reduce boost it can't hold the wastgate closed.

Is the car slow? If the boost guage is faulty (or the line to the computer) you might have boost and not realise it.

You dont really want holes in your J boot you will suck in unfiltered air and you dont want to trash another turbo.

Having no boost at all is quite difficult to achieve which is why I was suspecting your guage (well that and the pipe comes from roughly the same area as your cycling valve which sounds a little beaten up)

When the car is running right you will love it,

Good Luck,

Tony

Porsche-O-Phile

Well, I checked the BOV (diverter valve) and it seals properly. If I blow into it, there's no "blow-by" in it. If I apply suction to the nipple where the vaccum line goes, the diaphragm moves up slightly, so I believe that's normal operation.

My understanding of the cycling valve is that the line going from it to the wastegate is the only regulation of boost level. I was concerned since the line at the cycle valve was missing (pulled right out of the side). However, instead of getting full boost, I still get no (or very little) boost - odd. I figure it's better to have it connected properly in any event.

The car drives pretty well - kind of like a n/a on mild steroids. It doesn't have that 951 "slam you in your seat" boost that I expect though - it just revs through the power band evenly - no signs of skipping, missing, or anything like that.

The J-boot has no holes now - the part I mentioned was the bung where the hose to the venturi goes - the bung tore off since the J-boot is old. I was still able to jam the metal end of the venturi hose in there and it is reasonably well sealed. There's probably a very small pinhole sized leak or two under there, but nothing anything bigger than a gnat could get in.

Thanks for the encouragement - I'm sorry for the "I hate my car" rant. I know I'll learn to like it; I'm just trying to dispel whatever horrible voodoo curses the P.O. cast upon it. I'm beginning to wonder if the wastegate is stuck. I'll have to do some tests soon.

UK952

Its worth having the wastegate out to shim it anyway (cheap and easy provided the studs don't snap - a load of washers and maybe 3 longer bolts), but the heat check works well, and shimming could wait till later if its something else,
Tony

J Chen

Hey Guys,
Could he be one of the victim of the infamous collapse
test pipe or blocked cat converter syndrome ?

Porsche-O-Phile

Someone suggested that although when I looked down into the crossover pipe from the turbo side during the recent turbocharger replacement, it looked fine - both externally and internally. The cat situation is weird; it actually looks like I have a test pipe on there; I'll post a pic - maybe someone more familiar can tell me for sure.

Wouldn't a blocked catylitic affect the performance in general also, not just under boost? For that reason, I'm a bit suspicious of that as a reason, but then again if I'm going to rip apart the whole exhaust system, I might as well check it.

Game plan is the car is probably going to sit for 2-3 weeks (need new a/c compressor clutch & pulley or I'm just going to end up snapping polyrib belts, since the current one is siezing up). After that, we can do a exhaust / wastegate party someplace.

J Chen

I'm not talking about the crossover pipe.
It's the one that connects to the turbo
down pipe where the cat is connected too
Many have replace that part with a test pipe.
That part is double walled & if theres a
partial collapse you will not be able to see
it.