zoltan944

the 85 is suffering from high idle and terrible response with little power until the rpms get up there. usually a sign on vaccuum so i pull it into the garage
and pop the hood, when i jolt the throttle a little it has that 'intake suck' noise (like you shot compressed air down a tube or something) im pretty sure that is still a sign a vaccuum or lean?!? I look around and the only thing i could find is the hose clamp from the maf to the filter bottom wasn't tight (but thats not metered yet) and the hose that goes to the charcoal canister from the intake bottom is gone. that is also unmetered but maybe something else about that is the culprit?
when you do a quick rev the motor looks like it wan'ts to rip the those rubber intake connectors off. I only took off the rear intake and the maf and looked around. I hooked up a 'boost leaker' at 5psi and didn't hear anything, so i think its something else i should be looking for

Big Dave

Here's the layout of the vacuum connections for an '85. I was experiencing a similar problem of poor low end acceleration and a jumpy idle. I found that my connection at #13 had slipped completely off.

Unfortunately a lot of the connections are below the intake pipes, so if you can't find the leak elsewhere, you'll have to start digging.

Imo000

Here is an easy way to locate a vacuum leak. Take a can of starter fluid and slowly, with small bursts, spray around the intake manifolds. If you find a spot where the engine rpm rises every time you spray, you can start looking for the leak around that location.

zoltan944

On #10 the top right of the 6 vaccuum lines there was blocked off with no line going from it. However that is a good sheet for reference going through this thing. I already have my 'intake refresh' kit coming from 928spec, so the pipes wer coming off.
Imo000- the only thing i forgot to mention in my post is i did the starter fluid trick. then i did the boost leak deal, then i tried the boos tleak with 409 looking for bubbles. I havn't busted out the fog machine to try that yet, but you never know

zoltan944

also, i know there is supposed to be SOME oil in these pipes when i take it apart, but there was a fair amount down in the elbow after the maf, and i see oil on 'top' of the motor around the throttle body sitting down there. sorta common, or a line im gonna find loose when i pull the intake

Imo000

Oil in the intake is common. Until the supercharger ( at which point I disconnected all the vacuum lines from the intake) I constantly had some in the end tanks and probably bellow the MAF too. Nothing to be concerned off. The slower you drive the more it will accumulate, so every now and then make sure you take it to the redline! It will clean out all the pooled up oil from the intake.

SteveG

Zoltan:
"Supposed" would imply that Porsche designed it so and I don't think they did that, so I would replace "supposed" with "allowable." I refreshed everything rubber under the intake and installed an aftermarket louver in the oil filler neck that "could" keep misting from going thru that vacuum hose connected from the filler neck. I think that louver is doing nothing as I seem to remember reading here that that is the route it takes; I still have a layer of oil in the plenem whenever I check it. So it seems that layer is "allowable" and inevitable.

zoltan944

I am such a freakin slow poke too!! My commute is very short, and im not big into making myself standout.... but now i have a DOCUMENTED reason to pull through redline on the way home everyday
on a side note- oil accumulation couldn't be my issue could it?