Okay... I installed an autometer vacuum gauge in my 04 150 with the 5.4... Now, maybe i'm wrong but I thought these things were supposed to "dance" around a little bit. Mine seems to build up very slowly and then not really move that much. I was at the Ford house and the tech there told me just to tap into the vacuum hose that runs up to the brake booster, is this wrong? I couldn't find another vacuum like coming off the manifold that was small enough to take the hardware that came with the gauge. On the "t" that I put into the brake booster hose I kept all inlet and outlet holes the same size as on the hardware that came with the gauge. So... is this just the way it is? or did I tap into the wrong thing. If so then can anyone tell me which vacuum hose to use to get a more accurate representation of the vacuum.
Thanks

 

When I was using mine I taped it off the main vacuum hose that comes out of the passenger side of the throttle body. I used a large t fitting with a small outlet. It read correctly.
I replaced it with a ScanGauge, but still have the Autometer gauge, mount, line, Y-fitting etc. laying here.
The hose size was 11/32 inch.
Chris

 

chris.. is that the hose that runs around behind the airbox and up to that little "thingie" that's right next to the brake booster?? then it runs on down behind the engine, looks like to the transmission possibly??

 

Mine works fine. Just go off of the fuel pressure regulater, put the T on the vacuum line going to your front hubs
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