Ulf

Hello, im new to porsche and so on and got my hands on a 2005 cayenne turbo 4.5l with 500hp
. Not sure of all the teknical terms and etc for this model. But what i am wondering is if anyone knows what the stock boost is?
Because now i've never seen it going over 4-5 bar. I have the big breakes and so on.

Would like to know more about this awesom and fun car!

Thanks!
/ ulf from sweden

Ulf

Took it for a drive today and it only reatched about 3bar. So i think something is wrong..

prosled8

Seems like it is tough to get answers to this question. I asked what people were seeing on the 4.8 turbos and never did get an answer.

I think the stock 450 hp 4.5 turbo should show 0.7-0.8 bar on the gauge at max boost. On my 500 hp 4.8 turbo the gauge goes clear past the last markings at 0.8 bar pegging the gauge at its maximum.

Could be that you have faulty diverter valves that are not allowing full boost. Could be boost leaks in the various turbo plumbing connections. Sounds too low for sure at .3-.4 bar.

Ulf

Thanks for the answer!
Well figured aswell that something is wrong..
Is there anyplace where i can find a "map" for the enginbay ( dont know the words haha ) or something like that.
Or can it have to do with that my "service now" message that i've not resetted that makes it go a bit to "safe mode"?


Thanks!

deilenberger

I've never seen an engine bay map - but if someone wants to take detailed photos of their engine compartment - and some of us added the descriptions of what is being seen - it would make a great resource for people. The photos should be taken with the "beauty covers" (black trim around the outside of the compartment) off.

Volunteers? You can PM me for an email address you can send it to - and I'll give it a shot..

The other option is looking at dealers on-line parts catalogs. You often can figure out how things go together by looking at the exploded parts listing views.

And exactly what does the message you're seeing say? Your description could be something like an oil-change message, or it could mean something is actually wrong. Are there any dash warning lights on?

Ulf

The message is just to do the service, oil etc and that is already done but never got to reset the message.

Perhaps i can take som photos of the engin when im going to have a look.
Seems like i have to at this point

J'sWorld

955 has a tamper proof diagram sticker on the radiator support to the right of the hood latch.

Dilberto

You got a bad N75 valve... which controls maximum boost. It's right next to the intake Y pipe....

Ulf

Wow, thanx! Gonna order one now!

JAGMAN1

It may not be the N75 valve as there are many vacuum hoses that connect between the many boost related control systems.

Remove the beauty cover at the front of the engine to start. Trace all of the vacuum hoses that connect in that area (near the throttle body inlet). Then move to the rear of the engine at the top center of the engine. In that area you'll find many more vacuum lines that connect to the rear of the intake manifold.

If I had to guess you'll find a bad vacuum line somewhere in one of these two areas, or in between.

mtnrat

Many of those vacuum lines are quite brittle, so handle them carefully.

jeanmarcboilard

Page 145-149
https://www.porsche.com/all/media/pd...USA_GB_9PA.pdf

Ulf

thank you so much! That were exactly the thing i were looking for!

jeanmarcboilard

Let us know what you find, for future reference.