naru

The drive gear is on the crankshaft,not the cam. At this point,I would remove the crank seal to look at the drive gear and disty gear. Sounds like you will need to do that anyway. Be gentle on the crank gear.They are NLA new.

Not really. Not unless you have a slide hammer handy. Penetrating oil and use the movement you do have to loosen it furthur.

Rotor not turning? 84s do not have a timing belt Sure it is 84? I`ve seen the drive gear on the crankshaft strip,

Your FP regulator is not working. 50 psi is too high. There is a small chance the return line is open,but,restricted. I would direct the return into a fuel can instead of the tank to see if it makes any difference. Only other possibilites are an inaccurate gauge(seems unlikely) or an overpowering pump(its not).

Why? Which diagrams are those? I don`t know of any relevent ones. Most of the FSM troubleshooting trees are crappy or just obvious stuff anyway.

That fuel pressure is still 10 psi high. Could be the problem right there. I noticed mine started to idle bad at 40-50 psi. Try again w/dry cylinders and plugs. I`ve tested my injectors for leaks by removing them from the heads but keeping them attached to the pipes. Or you can block the return and supply lines w/pressure on the gauge. If it drops,the injectors are leaking.

That pump is not the problem. Looks fine. All of the aftermarket pumps for this application look exactly the same to me regardless of the brand name applied. All have the same specs too. I suspect they all come from the same Chinese factory.

Diagram here on page 28 of the ea81 service manual. http://jdfinley.com/file-downloads/subaru-manuals/

Hard to tell if you are talking about the regulator built into the fuel rail at the centre of the engine or the "regulator" at the back. The rubber line from the filter goes to the rearmost hardline.NoTees. The return line from the FP reg, is the upper front one.Is it clear back to the tank? Was the gauge Teed in or not? What pump did you use?

Hard to tell,but,that looks more like a pulsation damper. Does it have a vacuum line? If it is an aftermarket regulator,it needs a vacuum line so that it knows when to vary the pressure.

Are you sure that is a regulator? Definitely non stock. 100 psi might not be too high depending on how you hooked up the gauge. If you just deadheaded the filter output you might get 100. If you teed in the gauge,100 is way high. The return line may be blocked.Check. You want about 28 at low idle,43 at full boost. 36 engine stopped or engine running w/FP reg.vacuum line disconnected. My 84 turbo FP regulator went bad very recently. First symptom I noticed was The regulator seemed sticky. Sometimes too high,sometimes too low. Stock is unavailable so I bought one of those adjustable $20 Chinese ebay ones. https://www.ebay.com/itm/Universal-Fuel-Pressure-Adjustable-Regulator-With-Filled-Oil-Gauge-Aluminum-Blue/261732705229?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 Car never ran better. So far,so good. Only complaint is that it does not hold pressure on shutdown very well. I`m running an onboard gauge now.

Probably because your choke heater is unpowered w/o the ECU. Test it w/your meter. You need to trigger the choke relay elsewise if you don`t want to use the ECU.

Well,not quite. The ECU receives a RPM signal from the distributor.The wires connect at coil negative. Hard to imagine how that would be significant here,but,one could remove the ECU wire from coil negative to see.

For this car it is simple enough. Any positive pressure in the intake w/the car driven WOT at the limiting speed is bad.

Just keep the gauge hooked to the intake and go for a drive. Much simpler.

Diagnosing a restricted exhaust w/a vacuum gauge can be tricky until the exhaust becomes quite plugged. I see no evidence of a restriction from your gauge readings so far. It is completely normal for the vacuum to drop when the throttle is opened. You want to see the gauge at your 4000 rpm limit while driving. Get some hose. Last one I did showed a positive pressure on the intake.Proof positive. Better test is a pressure gauge on the O2 port,but,they can be hard to remove. You don`t need a specialty gauge. I used a garden variety gauge.It survived fine for the short duration required. The muffler shop may be able to attach a gauge by drilling a hole and plugging it when done. Subes are good in that you can drop the exhaust off the heads for a test. The symptoms described in your other thread sound very much like a partly plugged exhaust.

These guys look like big turbo guys in Ohio. https://www.xsboostturbochargers.com/product/subaru-impreza-wrx-forester-baja-new-turbocharger-chra-tdo4l-13t/ They sell European Melett brand (GD approved) Subaru CHRAs for about $350.

I don`t know how you can be so dimissive of the opinions of turbo builders in general and this one specificly without any supporting evidence. They see 1000s of turbos and are well aquainted with failure modes,after all. Not everything is someone elses fault(or anybodys). Good oil pressure with the turbo fitting deadheaded does not mean you have good oil pressure with the turbo installed and flow is required. A restricted (sludge was mentioned) oil feed line with only a pinhole passage would show good pressure with the fitting deadheaded,but,poor pressure with the turbo installed and flow required. To make an electrical analogy,it is like measuring good voltage on a low capacity battery with no load,but, poor voltage with a load applied. At least one turbo builder wants you to replace the feed lines,never mind clean them. I would modify a banjo bolt so that I could monitor oil pressure at the turbo with everything installed. Small price to pay considering. Unless i missed something,overboost or a intake backfire would tighten the nut of a reverse threaded shaft. They only loosen the nut on a straight threaded shaft. I suppose an exhaust backfire might loosen a reverse threaded nut.

I think you have an EA-81T up pipe on your car. They mount the O2 sensor there. Plug the hole w/a dead sensor or WHY.

Those were rapid demises indeed. It does make one wonder. The way I read it there are 2 poor lubrication/loose nut scenarios. In the first,poor lubrication causes bearing wear allowing the turbine wheel to hit the housing thereby slowing the shaft and loosening the nut. In the second,poor lubrication or debris slows the shaft of a tight or normal bearing and the nut loosens. Here is a Honda story that sounds eerily similar to yours https://honda-tech.com/forums/forced-induction-16/compressor-wheel-nut-keeps-coming-off-2506930/ 2 loose impellor nuts within 25 miles. Restricted oil line. I agree that a bearing fitted too tightly COULD be the problem. I would want a seperate oil pressure gauge on the turbo fitting for the next test run just in case. Don`t know if you read the other links,but,the first insists that shaft binding is the ONLY reason for loose nuts.

Look under the carpet on the passenger side. Fuel pump and ignition relays are there.

I`d check fuel pressure while driving. Flow test at 5+ psi too.

There is no fuel cutoff switch. Don`t know where you got that. Make sure you put all the wires back on the coil correctly. The grey shielded one on coil - is your rpm signal to the ecm. No fuel pump w/o that one. Check what is going on at the fuel pump relay under the seat. You need power to the relay from the fusible link and a seperate ground signal from the ecm to trigger it. I would jump the relay contacts to see if the pump runs. On my own 84 turbo,the fuel pump driver transistor in the ecm failed. I just took a trigger signal from elsewhere.

Poor oil supply or worn bearings lead to microbinding of the shaft. Shaft decelerates for a microsecond-interia of the compressor wheel and intake air wants to loosen the nut. It does happen pretty often according to the turbo builders and a quick look around the forums. Here is another reputable reference to "compressor nut missing" https://www.ms-motorservice.com/fileadmin/media/MAM/PDF_Assets/Turbocharger-damage-in-PSA-Motors_54369.pdf Good info on measuring oil flow too.

That keeps the nut tight against boost pressure,but,if the shaft binds for microseconds at a time,it tends to loosen.