Vac. leak but where?

[98eclipseRS]

Alright either i'm stupid or there is something seriously wrong with my car. Alright after gettting my head rebuilt the car ran fine for the first 1500 miles then recently i have been hitting fuel cut realy early on stock boost levels. I have checked everything to try and fix it but with no success. So now my boost guage is starting to only read 10 Hg. of vacum at idle. It also idles rough. I have checked everysingle pipe and connection in the whole intake system and connot find where i could be having this leak. The car holds boost fine also which is strange to me. If any one has any input on this it would be great. Its not fun hitting fuel cut at 5k rpm at only 14 psi. Mods are in my profile so you can check that out. I have an uicp comming and i will see if that helps at all with this problem. thanks in advance.
-zach-

 

[bjgarvin]

boost leak test. you won't find leaks by visual inspection.

Ben

 

[DSMJim]

Another way is if you have access to an oxy-acetalyne (spelling?) toarch. Start your car and spray just oxygen around parts of your car, you will obviously not have the toarch lit and not be using anything but oxygen. When your car injests pure oxygen the RPM will momentarly shoot up then die down again by a few hundred rpm. Just spray little bits here and there around your motor until you notice something change. Then you know your vac leak is in that particular area. A way to test it to see what it sounds like is just to spray it on your filter and see the rpm go up then you know what your looking for when it changes.

 

[98eclipseRS]

thanks that sounds like a good idea unfortunately i don't have one. Maybe i could find someone with an oxygen torch and borrow it or something. I guess i'll just have to mess around and see if i can figure it out.

 

[Enigma_Man]

or you could just build a boost leak tester, which is 100x easier than using / acquiring an oxyacetylene torch.

I have one made just like this, works great:

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

from the vfaq.

-Jesse

 

[Defiant]

You can use WD-40 instead of a torch, or a propane torch that's not lit. Be aware there are hazards, but not really drastic ones.

 

[98eclipseRS]

ya im going to go down to home depot performance today and get all the stuff to make the boost leak tester hopefully i will have my car running normally soon. I just hope its not the intercooler that is leaking.
once again thanks for all the replies.

 

[Vegas Smith]

I thought i had no boost leaks. I boost leaked the car, it turns out i had 5 leaks. Try hacking your mas to take care of fuel cut.