Just got a fuel pressure/vacuum gauge to do some testing on my car and want to fit it up to the hose between my fuel filter and fuel line. I know I'll have to T the hose or buy some more for testing purposes, but what's the inside diameter of the hose that runs from the filter to the fuel rail?

Am at work now but want to try and grab some from the auto shop on the way home. Thanks for anyone that can help me out with an answer

 

Found this:

5/16" is only 7.94mm though, but i guess .022" is minimal, just push on harder.

 

I'm using metric so 8 or 8.5mm sounds about right. Many thanks

 

Make sure you get fuel injection hose, not regular fuel hose. If you're not surprised at how expensive the hose you're buying is... you're probably getting the wrong stuff.

 

Nice one. Cheers for that advice

How much hose is there between the filter and the rail? Might buy a new hose so that I can cut one and T it into my gauge and then I'll have another one to put back on for good once I've done testing.

 

I would T it going out of the engine.That way you know that the engine is getting Fuel(as the PSI will show that the rails and injectors have gotten their fuel).
If you put a Gauge before the engine,Ya sure,it will show that the engine is Getting Fuel Up to the gauge.But what about to the Injectors??.It won't tell you anything after that.(like if the injectors GOT fuel)..
so for that reason.put your Fuel Pressure gauge after the engine.
Btw,this is with an aftermarket regulator and gauge setup.

 

I know the rail is actually getting fuel, but I am wanting to know what pressure the fuel is as it is going into the rail. Am following the diagnostic steps listed in the FSM.

Need to do separate checks to find out if the injectors are working at all and getting fuel into the engine.

 

This method won't show you the rail pressure though. Fuel after the FPR will be at a different pressure.