Fuel pressure dropping off with my denso pump

[Mike70gtx]

I have a fairly new denso pump and it has been working great. I just started getting knock so I put the fuel pressure gauge back on. I hit about 45 to 48 pounds and then the pressure falls off and the knock goes up. The last time this
happened the fuel line inside the tank split. Is anyone else having problems maybe with too much pressure. Is there anything else I can check before I pull the tank again? What about the adjustable regulator? If so, how do you check it?

 

[Roger]

I fear a split hose in the tank might be the culprit.
So far my Denso has been reliable.

 

[Clark6]

I have gotten many 71 psi runs on my Denso If my gauge is accurate @ about 22-24psi boost. Mine's been pretty reliable also, I have a BAP behind it.

 

[BEATAV8]

If you haven't replaced the sending unit wiring you probably should. Racetronix sell the parts, including the bulkhead pass through.

Any hotwire kit is only as good as the sending unit harness which it is connected to.

When I replaced the OE sending unit harness on my car it was worth nearly 5psi fuel pressure.

 

[Mike70gtx]

The second time I took the tank down I did the wiring connectors from Racetronix. How can I tell if the regulator is bad?

 

[BEATAV8]

well, it shouldn't be leaking fuel into the vacuum side for one thing. That would indicate that the diaphragm is ripped.