My car's name is "Vacuum Leak" - Team-2G Mitsubishi Forum

GS-Turbo · 04-06-2006, 11:51 PM

okay well I'm following my haynes manual for fixing my low rpm dropping problem at idle and engine stumbling at acceleration problem. The book says it could be a number of things but I'm working on seeing if its the vacuum hoses first. So my questions are these ;

1) what does the PCV hose do , does it carry highly pressurized air inside ? The PCV hose is that "Z" shaped hose over the valve cover.

2) what does the brake booster hose do ? it is the first hose connected behind the intake manifold on the same side of the throttle body and does it carry highly pressurized air inside ?

3) about how many vacuum hoses are there in total?

its kinda crazy actually because I noticed that 4 of the hoses I found dont have clamps where they connect. Either it came like that from the factory or the mechanic that inspected my car removed them on purpose.

thebluelion · 04-07-2006, 01:18 AM

man...Ive been having the same problem with my car sice I bought it...I thought I fixed it recently when I found out that two of my plug wires were swapped...and it ran really good for about a week..then it all came back...started idling kinda shaky around 650-700 rpm where normally its at about 850-900...and it kinda hiccups when accelerating..like its cutting out..which is embarrasing..i thought maybe it was my coil but its not...you think it may be a vaccum leak?

4G63Spyder · 04-07-2006, 02:36 AM

Check your intercooler piping. I had a split flex hose a while back. fixed it, fixed the idle problem, which was the same as you describe. Also, you can do the following if that's not it (I read this omewhere, I'm not this smart):

1. Remove the intake and cap off the turbo airtight. Find a way to make sure the cap does not come off (I used a 2x4 cut to the right length)

2. Get a manual bike tire pump, and modify the hose with a t-fitting of the same size as your vaucum lines.

3. Cut a vacum line and tap it on to the bike pump (I just removed the feed to my (non-factory) boost gauge for this step, and tapped onto there).

4. Start pumping it up to about 20 psi (the pump I had had a pressure guage on it).

5. Listen for the leaks, replace those hoses.

Problem solved, man. I found like 10 leaks when I got the car and I do this anytime I suspect a vac/boost leak. It really works.

EDIT: Just saw this in another thread:

go here:
http://www.vfaq.com/mods/ICtester.html

GS-Turbo · 04-08-2006, 11:29 AM

thanks for the info but what about my questions?