74 1.8 - fuel pressure regulator?, opinions. Options

[wonkipop]

car = 74 1.8 L jet (all intact).

problem =
out driving this morning - gradual then worse loss of power. no accelerator response.
pulled over. cut out. no idle. let it sit for a few minutes. restarted it. got it going.
got up road all right, but symptoms kept coming back, then going away. limped it home.
fun ruined for driving, but fun diagnosing started.

felt like your classic fuel starvation.

background. car has been recommissioned and back on road for about 5 months.
running beautifully.
fuel system entirely rebuilt. clean tank. new fuel lines. new fuel pump. new injectors.
all vacuum lines renewed. all ignition compenents renewed. except coil (which could be original, looks like it, but coil was tested and was a goody).

one thing = fuel smell in engine bay on lhs around air cleaner. comes after a few days sitting. had put this down to saturated charcoal cannister, feeding back fumes into aircleaner. have inspected all fuel lines etc thoroughly and no signs of any external fuel leaks/wetness. just a vapour smell thats not there all the time, just after sitting.

pulled everything apart today down there after getting home today.
checked everything. all tight, no air leaks. no bad hoses.

looked at pressure regulator. which sits right there under aircleaner.
i have no reason to think its not original and about 45+ years old.
and did not get replaced. looks great externally, but.........internally?

will get car into shop this week. where i can get some guages on it etc.
at home with car. nothing but basic tools.

but whats thoughts out there.
anyone had this one before.

[wonkipop]

i only had time today to attend to the Aux Air Valve.

moved a few of the charcoal can lines out of the way before the drive out.
discovered the hose between AAT valve and intake plenum appeared to be collapsing. once out at workshop gave it some revs while i watched it and it distorted into a wild shape, however the car was warm and pulling vacuum at revs.
cold it was definitely partly collapsed in the bend between the valve and plenum. might have been affecting draw of air during warm up? this was hose that porsche aus supplied us. we shredded the original getting it off 9 months back. i did a trick with it that might have worked, sometimes doesn't, but a couple of hose clamps are helping it keep its shape under vacuum. might look around for a better hose.

pulled the AA valve - its fine. fridged it - opened right up. test wired it to a battery and got a 100% close. took about 3 - 4 minutes to close from room temp state. tested connection and its getting current. gave it a cleanout with carb cleaner inside. it looked clean in there before i did that anyway. nothing sinister came out with the clean.


far as i took things. do one thing. drive it, see what happens, on to next.

we did not play with timing. left it alone as set it on monday.
want to wait until i install a new throttle body gasket.

hooked it up to the EG analyser but its got to be serviced - could only take CO readings. coming in at 2.3 % CO. i can borrow an EG from across the road guys, but they were busy today.

its driving nicely fully warmed up, but still little moments, one or two where it goes into a slight very minor hunt on the way back home pulled up at the lights. its idling ok at about 900.

something still there niggling it.

but its a lot better.

i'll move on the CHT sensor next and test that.

after that go through the brain plug tests.

test tomorrow when its stone cold will be to see what it does during warm up phase.