By any chance does anyone know what size adapter you need for the fuel pump test port by the coil pack on the 4.3 vortec?

 

Guess i'll take the calipers out tomorrow thanks for all the help!

 

There's a lot of action on here, it takes time to get replies, especially under three hours.
Give people some time, chances are after they seen your second post they said f it.


Anywho, my 95, the fuel port is a -4 AN fitting (the thread size overall is 1/4, here is a fitting I used to make an adapter for the fuel pump 1/4 in FL x 1/4 in MIP) but you must have the correct female end to complete the seal for proper testing.
I assume you are getting a gauge to test the pressure?
Here is the one I just purchased
Actron Fuel Pressure Tester Kit CP7818: Search no more for the best Electrical Tools & Testers at Advance Auto Parts

 

The 96+ Fuel System Diagnosis thread give the specifics on the fuel pressure test port. It is very, very rare that a question has not already been covered.

 

Thanks for the info yeah guess I was getting antsy.