^^^ What Brutus said ... and check your fuel delivery (as well as the pressure) from the supply line from the pump, which will tell you if all is OK to that point.

Here's your setup with the one damper at the front and the two pressure regs at the rear.

 

Okay so after tinkering with this for several hours today here is where I am now, I know for a fact that I'm do not have a problem with the fuel lines from the tank to the engine, I checked the pressure at the passenger side fender and again at the entry to the damper I'm pegging the gauge out at over 100 PSI at both points so I now know that my problem is on top of the engine some where I'm still getting a 10 psi reading anywhere I check on the rail on either side including to the injectors and what i'm suspecting at this point is either a blockage in the rails which I doubt or that neither of my regulators is functioning and that the 100 psi is being dampened to around 30-40 psi splitting into the two rails and meeting no resistance at the regulators on either rail and galloping down the return line to the fuel tank so under no resistance(back pressure?) that 30-40 turns into 10 and under load drops to nearly nothing. I did pull one of my injectors to check my spray pattern and found that there pretty much wasn't one it was more of a quick spurt an fuel followed a vague mist that dissipated about an inch away from the injector I initially assumed it was clogged so took it into the garage and sprayed it down with carb cleaner followed by brake cleaner with a pair of jumpers ran from a battery charger to the terminals on the injector, I then hit it with another shot of cleaner in a hose attached to the inlet side (filled the hose) then toggled the power on the battery charger while pushing the cleaner through with compressed air and got a very pretty , even atomization from the tip. When I reattached it to the rail I got the same squirt then nothing I was getting before which lead me to wonder if 10 psi dropping to nothing was actually enough pressure to allows the injectors to , well, inject! Anybody ever had both regulators go out at the same time ? Does any of my above rambling make any sense or at least sound reasonable? Do I have a correct understanding of how the damper and regulators work ? on a separate note I did manage to find that my hard vacuum line running to the timing advance on the distributor was crushed under the aux air pump so at least I repaired one thing today !

 

You could check some of your theories by measuring volume of fuel returned to the tank. .... if you safely extend the the fuel reurn line, disconnected from the tank under the RHS carpet in the trunk. Bridge the fuel pump relay for 30 sescs and you should get 1350cc or so.

If the FPR is set "too low" then you will get a much larger volume of fuel returned to the tank.

 

okay John I assume by fpr you mean the regulators, is there a way to adjust them ?

 

The regulators are not adjustable. Strange that you have such a complete failure, so I'm wondering if maybe some rubbish somehow got through the system and got to both of them, or your new damper.

If the problem is that the regulators are allowing too much fuel to return, and therefore giving low rail pressure, then the return flow will be excessive .... if on the other hand the damper is not allowing delivery through, and this why you have low rail pressure, then the return volume will be very low.

The damper at the front is just a pulse/pressure wave 'shock absorber' diaphragm, and the regulators at the rear regulate the pressure by allowing excess fuel to flow back to the tank, and they will also have a bit of damping effect because they too have a diaphragm within. The vacuum connections modulate them a little according to throttle opening, and therefore fuel demand.

 

Well Dave the original damper had a busted diaphragm in it and was allowing fuel to flood the vacuum lines and since I replaced that I haven't pulled a single vacuum line off anything and had fuel run out of it , so I consider that a win (however small) I had hoped that the Regulators were okay but now it would appear that isn't the case will be examining this more closely later this evening when everything cools down as I'm working on this with my dad who is 69 and doesn't do so well in the heat (its in the mid nineties here) on a related note i see on advance , auto zone and o'reillys websites that they offer regulators for my car anyone ever used one from them?

 

Dr Bob I'm in Elizabethton Tennessee which is about 20 minutes to the south of the Bristol Motor Speedway. Why do you ask?

 

Hi James ... if the damper was that bad there's a good chance the diaphragms in the regs are the same, or on the way, so it'd be good to replace them anyway. Speak to Roger at 928's Rus he's likely to have them and I find his prices are good.

 

Sorry, I'm not terribly familiar with MY84, but if I'm understanding the fuel flow from the diagram above, only ONE FPR has to fail for the pressure to be low on both rails. If the two part "5"s are rubber lines, as they appear to be (I see clamps), you could squeeze them off one at a time and figure out which FPR is bad. If the pressure does not rise, squeeze off both "5"s.

 

If you can still see 100psi, I think you are still seeing pump's limit into a dead end, where you should always be T'ing into the line whose pressure you are trying to read........
jp 83 Euro S AT 54k

 

Okay here's what I found today men. I reinstalled the damper and then replaced those short soft lines (#5) Bill spoke of that run from the regulators to the return line then clamped them both off and attached my pressure gauge to the front injection point on the drivers side rail and lo and behold 100 psi on the rails! I then removed the clamp on the drivers side regulator and repeated the test which was now showing 10psi on the rails. I replaced the clamp on the drivers side and removed the one on the passengers side and repeated the test again and this time got 39-40psi on the rails. After I stopped giggling like a schoolgirl, I did a test on the injector I had out and got the most beautiful, even spray pattern I've ever seen! At this point I began laughing maniacally as was reinstalling the injector, then i stopped long enough to remove all the tools from the car , close the hood leaving the vice grips as a fuel regulator setup intact and took my car for a nice drive down the mountain and actually came back under its own power! I cannot thank you guys enough for the advice and needless to say if ever i get to meet any of you the brews are on me!

 

So, one bad regulator??? And you now know which one it is!!
good stuff.
jp 83 Euro S AT 54k

 

Yes indeed ,one bad regulator, but for good measure I'm replacing both of them, and thanks to you as well for your input!

 

Great to hear the outcome ... Depends how financial you are, but as you've had the damper and one regulator fail, it's probably just a matter of time for the other reg to go, and so if it was me I'd replace both.

BTW ... can't figure out why they had two regs and one damper on your model, when on later cars there are two dampers and one reg.

Thanks for letting us know.

 

Bill scored there :-) Excellent result !