Vaccum Leak Dection Question

[robroy55]

I have a 2002 24V engine with 37.500K. It misses only when cold and when I turn on the air or put it in drive. Then clears up once hot except when I trun onthe air.. My gas milage has dropped to 14 mpg in town, no air on. To find a vaccum leak, once you use a Mity Vac, and you see the pressure dropping, HOW does one go about determining WHERE the leak is coming from??

Thanks for all the help this fourm gives us shade tree guy's !!
Rob Roy

[shorod]

There are a few ways to detect vacuum leak locations.

One way would be to find a mechanic's stethoscope and use that to listen for hissing noises through the pinpoint end of the stethoscope. Obviously, you'd need to be very cautious using such a device in close proximity to moving parts.

The more popular "shade tree" method is to use a propane tank for camp stoves or small torches used for household copper soldering and, with the car running and the torch unlit, release the propane gas in the areas of vacuum lines. If the propane gets sucked in through a void in a vacuum line, the engine will stumble. Throttle body cleaner sprayed along vacuum lines will work in a similar fashion. Of course, due to the explosive nature of these methods, I cannot recommend them.

I wish I had a fancy disclaimer to pasted here. You know, the statements above are not advice or recommendations and are listed for entertainment purposes only, blah, blah, blah. I cannot be held responsible for a person's ignorance or any damage that happens as a result of such ignorance, etc.

-Rod

[unbe]

Another way is using a needle nose pliers and pinching lines and seeing if your idle inproves

[way2old]

Yet another is to rub all the lines with talcum powder. Cover them thouroughly. Start vehicle and run for a little while. Shut car off and look to see if you can find a plae where the powder is gone. There is your leak. No explosion, no danger of moving parts.