how fast should d-jet pressure leak down?, 75 2.0 : is this too fast? Options

[DRPHIL914]

10 psi/15 minutes so down from @30 to 0 in 45 minutes.

Went for drive today, have been running really good all week to work but this morning almost didn't start, heavy smell of gas so pretty sure one was leeking. 70 degrees so warmest morning all week.
just wondering if anyone else has watched theirs to see what would be normal.
I had my other set of injectors original to the car- out a few years ago and just sent them in and had them flow tested, and we're within 1% of each other so I'm going to put them back in. They are the metal body ones. The ones I've been running I put in 3 years ago and they were brand new from Otto venice, but plastic not metal like original ones.

Btw the rough start seem and rough idle lasted about 2-3 minutes and ran fine after that.
Also - I only run no ethanol gas. All gas hoses replaced a couple years ago. Filter and tank sock were new then too.

[914Sixer]

Not so much the time it took to leak down, the fact is it is leaking is adding to the problem.

[Dave_Darling]

It sounds OK to me. Maybe not optimal, but OK. (This is fuel pressure, right?)

--DD

[DRPHIL914]

It sounds OK to me. Maybe not optimal, but OK. (This is fuel pressure, right?)

--DD

Yes. I have an in-line gauge. So I was just making the observation that today that was the rate but other times it's stayed higher for longer.

[Java2570]

Are you still running a 3 port stock fuel pump or did you put in a new 2 port? I think the 3 ports had some sort of check valve that helped keep pressure in system longer....?
I don't think most 2 ports pumps have that....although I believe one could get a check valve fitting. I had issues with my old 3 port pump where the pressure would drop down after shutting the engine off....would cause problems when I restarted later. Of course, I also had some fuel hose kinks contributing as well. What you're seeing doesn't sound too bad for drop off of system pressure.

[r_towle]

try a test.
re route a longer gas line on the return side and remove the cold start injector from the fuel circuit.

See if that stops the two issues you describe.
The smell of fuel after it sits.
the rough running once you start it up after it sits.

If you get the leak down to occur via the fuel pump and fuel pressure regulator (both sides of the circuit) and eliminate the injectors dripping, that might make things just fine.
I live up here in the cold, I removed my cold start injector long ago....
Its not required if you know how to start the car.....(for me that is turn the key to run twice, then the third time it starts right up...cause the fuel system is now at full pressure)

Oh, BTW, I do this with the 911 also....which is an 84 with motronic.
Starts better when I do that routine, after it has been sitting for a long period of time.
Rich

[DRPHIL914]

try a test.
re route a longer gas line on the return side and remove the cold start injector from the fuel circuit.

See if that stops the two issues you describe.
The smell of fuel after it sits.
the rough running once you start it up after it sits.

If you get the leak down to occur via the fuel pump and fuel pressure regulator (both sides of the circuit) and eliminate the injectors dripping, that might make things just fine.
I live up here in the cold, I removed my cold start injector long ago....
Its not required if you know how to start the car.....(for me that is turn the key to run twice, then the third time it starts right up...cause the fuel system is now at full pressure)

Oh, BTW, I do this with the 911 also....which is an 84 with motronic.
Starts better when I do that routine, after it has been sitting for a long period of time.
Rich

Thanks for the suggestion. I was just talking with my mechanic who suggested doing this as well.