Please help Vacuum leak on 2001 3.0i

[kennyhoang]

I got an vacuum leak before cat. Can someone help me which are the hoses I should check for.

Thanks in advance.

[Weasel]

There are a few things that can leak on the 3.0i... check the bend of #9 on this link. This cyclone valve likes to leak (and the hoses to it), check the hose from the bottom of it first.

If it isn't the obvious things, finding a shop with a smoke tester makes it easy. Otherwise if you can monitor the upstream O2 sensor voltages with a scanner type thing you can watch them switching around while spraying suspect areas with brake parts cleaner or carb cleaner. When you get to a leak with the spray the voltages will stick at 0.8 vs switching rapidly up and down in the 0.1 to 0.8 range.

[kennyhoang]

Thanks, Weasel I did replaced that tube elbow.

[ika]

I think I have vacuum leak on N62 too , can someone help me what to check..