What are the changes in how the car runs, that indicate a vacuum leak?

I am about to replace all the vacuum hoses on a 97 max. Is EC-13 "the" diagram to follow when replacing vacuum hoses?

Are the crankcase hoses a part of the vacuum system?

Does anyone know what size hoses I need. I'd rather not take s**t apart in front of the parts store to bring in for comparison...

Any other suggestions on diagnosing vacuum leaks, I would really appreciate it! I don't have a Heynes, I do have the FSM.

 

often times you can hear a vaccuum leak hissing. depending on how big the leak is, either high idle, or loopy idle. grab a can of Throttle body cleaner and spray around the engine, if the idle changes, youve got a leak there.

 

Where do I connect a vacuum gauge to check vacuum in IM? How do I do it? The FSM assumes you have some background on this.

Is EC-115 the way to test the whole vacuum system pressure, or just a part of it?

 

Vacuum gauge > hose > Nipple that provides vacuum.

 

When I had a vacuum leak I had a really rough idle, almost would stall out.

 

IMO This is the best way to tell, beside listening for the obvious. vacuum at idle for most cars its about 20" Hg at idle (an agressive aftermarket cam over lap will be less than that).

 

I have no idea where the nipple you're talking about is located. Is it one of the hoses on the Absolute pressure sensor? EC-115 in the FSM?

 

It's any nipple that has vacuum from the IM.

 

which is the easiest to use?

 

dude...you're making this harder than it really is.

ANY HOSE ON YOUR UPPER INTAKE MANIFOLD WILL PROVIDE VACUUM. Look for the the size of your pinky.




Do you even have a Vacuum gauge? Because if you did, you'd know how it worked.

 

I can understand how you can get frustrated from some simple on going questions Shadyone, lmao!
Simply put if you haven't already figured it out already Atriuum just connect the pressure tester hose to any vacuum line. I had the same question when I bought mine. The instructions are clear once you know what to do, but for a diy'er kind of sucks when there's no DON'T and DO's explained.

 

any fitting you can put the gauge on AFTER the throttle plate because anything before it can vary. and the throttle plate is basically a regulator, and if you have a problem after the "regulator", the gauge will tell you.

i'm not 100% sure on this so correct me if im wrong.

if idle is fine, does that mean there is no vacuum problem? i'm not sure if vacuum problems always cause weird idle behavior.