cant find vacuum leak

[scguru92]

I did the brake cleaner test over all the places I thought of. What are the usual culprits for a vacuum leak on a 4.0?
Thanks

 

[smokey]

try the rear of the engine at the intake gasket. they are known to leak in that area.

 

[UrbanRedneckKid]

One by one, disconnect and plug different vacuum circuits, See if you find and isolate a bad line or vacuum motor.

Also having a scanner w/ live data really helps here, you can watch the Short Term Fuel Trim, and O2 sensors. Scanners work alot better than listening to your computer controlled idle.

 

[Stranger ranger]

only dam draw back to 4.0's is this dam infamous vaccum leak