I have an 06 F150 and have a major leak somewhere under the intake. I can here it hissing but there is no way I can get in there and see anything. I have tried using a mirror to see with no luck. A friend has a smoker and we hooked it up and smoke just comes pouring out from under the intake. Does anyone have any ideas?

Thanks
Chris

 

There's a hose on the driver's side rear of the intake manifold that feeds the brake booster, it rots out and collapses, causing a vacuum leak. Some 2005/06 model year trucks have a recall to replace this hose.

 

Just had same problem on 04 there is a vacumn port on rear of intake manifold against fire wall you can't get your hand in the space, mechanic had to take fuel rail loose to get to it about $150 to put vacumn hose back on, newer model has connection on top of manifold where you can get to it. Hope this helps.