Chasing my vacuum leak
 

Hello everyone, I’ve made a few threads about this, and I just can’t seem to chase down my vacuum leak. Some quick details

1998 automatic Boxster, 55k miles, completely stock

Current symptoms: rough/bouncing idle on startup that evens out at about 800rpm, and a noticeable torque decrease.


I’ve replaced the AOS and MAF. After I replaced the MAF, the codes went away for almost 2 weeks and then came back. The codes i had before the maf replacement were 1128 and 1130, and right before I replaced the maf, p0102. Now that I’ve replaced the maf, I have codes p1124 and p1126, with p0102 occasionally. I have had the engine smoked by a shop, and they came back with nothing.


I tried to find a vacuum leak myself by using a small propane tank and spraying a tiny bit is various places to test for a leak and it came back with nothing. What should I do next? I have a cheap OBD scanner, it can read MAF air flow but it can’t read voltage of the MAF. It can also read short term and long term fuel trims. I’m truly at my wits end, I appreciate any help.

http://986forum.com/forums/uploads02...1682724390.jpg
I also have found this loose wire by my feet

I'm new to testing the vacuum system. The engine I am working on is out of the car, I replaced all the vacuum lines and checked all the components with smoke and a vacuum tester but was still not able to hold a vacuum. Finally found leaks in the vacuum reservoir. I have another engine in pieces so tested the reservoir on that one and it had a leak in the same place. My friend Newart also had to replace his reservoir, so it seems to be a common problem.
Check post #49 in this thread.
http://986forum.com/forums/boxster-general-discussions/82558-bought-2000-boxster-s-project-3.html

I’ve been looking at the engine bay and I think I found the problem, and if it’s really this, it’d be almost comical. When I put the AOS on, I must’ve missed this connection because it wasn’t pushed in fully. I know this connection has something to do with vacuum but I don’t quite understand what it does. Could this have been the problem?http://986forum.com/forums/uploads02...1682778769.jpg

The arrow in your picture is pointing at a one way check valve.
I would need a schematic of the vacuum system to determine what it is connected to.

Looking at the picture I can see that the rubber connector with the two hose clamps around it is not seated correctly. Also the top hose clamp is not setting on the rubber connector correctly.
Could be part of your problem.
When you take something apart if you don't reassemble it correctly you can't expect things to work correctly.
Go back thru any work you have done recently and make positively sure things are reassembled correctly.
Most issues with things mechanical are rather simple.
Many of those issues can be traced back to were man has put his hands.