1995 200EFI Fuel Delivery Issues

[Slamdunk]

My 1995 200EFI (S/N OD200114) has a fuel issue, I'm ready to throw a match in it and watch it burn.
4 different mechanics, lots of money and problem still exists.

My By boat will fire right up, run at WOT then after a mile or less, it runs out of fuel but will idle perfectly all day if I let it.

This is a list of what has been changed and ruled out.

1. New tank pick up tube
2. Primer bulb
3. All new fuel lines
4. New breather lines
5. New low pressure fuel pump kit
6. New high pressure pump
7. ECU changed out
8. Swith boxes changed out
9. Stator tested well within spec
10. Anti-siphon has been in and out with no improvement.
11. Engine has less than 100 hours on New factory Mercury power heads. It ran great first season after rebuild, hasn't ran right since. All cylinders compression test well within spec, all close to 120 give or take.

I can remove the fuel pressure regulator and aim it outside the boat, turn key on and it will spray fuel on ground as long as pump is buzzing.
Turn key on again, pump buzzes but only sputters fuel intermittently.
Turn key on 3 more times, pump buzzes, no fuel comes through regulator.
When we install a fuel pressure scale on the Schrader valve, it only holds pressure while pump is buzzing, then goes immediately to zero when pump shuts off. No visible leaks anywhere.
Where is my pressure going?

I found another fuel pressure regulator, it's on its way. Might as well change it while I'm at it, right?

This issue happens whether on the water running or in the driveway with just the key on, heat is definitely not an issue.

This is on a beautiful Viper Cobra 201D and after rebuilding motor that I am now into about 13k, I'd really like to get her up and running again.
I've been throwing parts at this motor for two years and am still forced to fish in the "wakeless speed" areas only.
Please help!!🙏

[wentbroketryingtogopro]

i know the pain you are going through.i had a 2000 175efi that was a screaming eagle until i started having intermittent electrical problems.it never left me stranded but lots of times i would have to idle back in.some days no problem other times while running it would start missing and would go back down to idle speed.buzzer would go off all the time.as you say i was afraid to leave the no wake area.had several different merc techs check it out and we replaced several different parts but the engine never did run 100% correct.what helped the engine more than anything was having the fuel rails recalibrated and cleaned.also had the ecu rebuilt.i would think after the holidays are over mr. don weed will chime in to help you.my own personal opinion is whatever don suggests do it.he helps out a lot of guys on this forum.if i would have lived closer to his business i probably would still have that 175efi.i would like to make a suggestion,if i could keep from boosting someone off the starting battery dont do it.if you have to be boosted or you are boosting someone else try to do it without the cables touching.(making sparks )my problems started only after being boosted one morning and the cables got together and sparks flew everywhere.the engine never did run 100% correct after that.thanks and good luck to you

[Slamdunk]

Thank you, I'm sure I'll get it figured out eventually.
I haven't been on this site for a long time, but after posting on 4 different Facebook pages, the gentleman I bought the fuel pressure regulator from advised me to log in here and make a post, assuring me "Don" would chime in and quite possibly be my saving grace.

[EuropeanAM]

[QUOTE=Slamdunk]I can remove the fuel pressure regulator and aim it outside the boat, turn key on and it will spray fuel on ground as long as pump is buzzing.
Turn key on again, pump buzzes but only sputters fuel intermittently.
Turn key on 3 more times, pump buzzes, no fuel comes through regulator.
When we install a fuel pressure scale on the Schrader valve, it only holds pressure while pump is buzzing, then goes immediately to zero when pump shuts off. No visible leaks anywhere.
Where is my pressure going?[QUOTE]

You're running the pumps long enough to consume all of the fuel in the VST. Without the engine running, the system has no way to replenish the fuel you are displacing through the regulator, onto the ground.

Sounds like you may have a leak at the high-pressure pump top-hat seal, OR inside the fuel management "intake" (injector o-ring, slider tube o-ring, etc).