Hey guys. Wanted thoughts before I replaced a 75 regulator. Pressure tested the system, get 40 with the key on . Once the key is off the Gage drops right away back to zero. No smell of gas so doubt there's a leak. The fuel pump runs while the key is on, not shutting off from what I think would be lack of pressure build. Thoughts ?

 

Could be the regulator, leaky injector, or a bad check valve in the fuel pump. The fact that the pressure drops right off tends to point to the fuel pump. However, before changing anything, make sure you checked the fuel pressure per the factory procedure. The test you done only points out the fact that the pump is capable of holding presure while the engine is not running.

 

Ok, make sense . What's the procedure for checking that.

 

The pressure holds steady while it is cranking/key on. The pressure drops with the key off. The pump runs non stop too. Anyways, how can I isolate the regualtor to test it to factory procedure?