blue, black, pink... doesn't matter to me. Just as long as it works. :)

You couldn't have said it any better, I do all my own stuff. You want things done properly or to your likings, do it yourself. I know a lot of people don't have the resources, tools or just aren't mechanically inclined. But it really helps when trouble shooting.

Car is back!

The wait was well worth it!

The idling issue seems to be gone.
Car sounds great, the TDX exhaust is louder at idle but quieter while in boost (mostly due to the recir). I can hear the turbo spin and the bov much clearer now!
Car doesn't break up past 5k
Car doesn't smell like gasoline

New MAF, fuel return, properly gapped plugs, fixing the boost leaks, new tune, and 3.5" CAT yielded another 30whp and 40 ft-lb on 8lbs. @13lbs, it yielded another 20whp and 60 ft-lb.

I'll try and upload a video/sound clip. The TDX exhaust does sound very different from any other VQ exhaust.

300 miles later

Car won't make any fuel pressure when I put the car in ACC. Only after cranking the car a few times will the car reluctantly start. This of course happened on my way down to a wedding. (I made it... thankfully)

Anyways the exhibited behavior happened right after driving 2 hours, then stopped for food. Tried to get back on the road and the car just wouldn't turn over. Finally got the car to turn over, however whenever the car got anywhere close to boost, the car would go full lean and stumble hard. Limped the car another 2 hours and had to drive it under 2k rpm to make it to the wedding.

I believe it to be a fuel issue. But not 100% sure if it was the fuel pressure regulator, fuel pump, or a kink somewhere. Im leaning towards fuel pump buts really a guess. Fuel pressure will hit 45psi once the car turns over. Im thinking the vacuum must be pulling the diagram open enough to get fuel through to keep the car going. However, once the boost kicks in, the pump must not be able to put enough pressure through the lines.

Anyways, took the pump out and this is what I found.
http://www.the370z.com/attachment.ph...1&d=1438220712

http://www.the370z.com/attachment.ph...1&d=1438220712

http://www.the370z.com/attachment.ph...1&d=1438220712

Return feed got loose, bunch of crap all over the collector? I don't think these things would cause the problem so any help would be appreciated.

I dont know what all the black stuff is in the bottom there.

But, that hose coming off could cause the car to not be able to run in a way of fuel starvation.

With that hose not connected, the over-tank venturi will not function and the module cannot recover fuel from the driver side of the tank. This would cause the car to have fuel starvation issues somewhere around 1/2 tank on the gauge. (Hard to predict where exactly on the gauge as fuel can slosh back and forth in the tank, but ultimately if there is little-to-no fuel on the passenger side, the car is going to starve)

PM me your address and I will drop you a new hose for that in the mail tomorrow since that one is looking pretty unhappy.

If your tank has plenty of fuel on the passenger side and it still wont run, there is more diagnosing to do.

If you havent run into it yet, there is a pretty recent PDF I put together that goes over the 350z fuel pump module: http://host.cj-motorsports.com/pdf/3...uel%20Pump.pdf

BTW if you want to test the theory immediately, you can put it back in even with that hose still off, and add 2 gallons of fuel to the tank... when you add fuel it will land on the passenger side by the pump. If the car starts up like everything is normal, than you know its fuel starvation from that hose coming off.

The car had plenty of fuel :(

Im not sure of the black stuff either...

My form of diagnosing is tearing things apart and replacing parts until things magically work? Unfortunately I don't have the experience to say its one part or the other.

Is there an fuel pump independent way of determining if the regulator is functioning properly?

Call me a noob, but my thought process was to 1) put everything back together, 2) disconnect the vacuum hose on the fuel regulator and hook it up to a hand pump. 3) Supply power to the pump and use the hand pump to draw the diagram up and or down and watch the fuel pressure. The assumption here is that the fuel pressure regulator is a binary device in that it either completely works or not.

In any case, if im going to replace this fuel pump, is there anything else out there that may be more reliable/better than the Walbro GS342 I have in right now?

Plug the hose back in and tighten it. Go from there. If you are having fuel pressure problems, and a hose is loose in the fuel system, then that's probably the problem.

Got the new line! Thanks Phunk! The existing male AN fitting is too short for the new line. :( regardless, reattached the old line. Car still makes 0 pressure when I provide the pump power. Turning over the car still takes 3 or 4 tries with some gas.

Car no longer stumbles when it goes from vacuum into boost but does go way lean as the boost pressure increases. Car is waiting to lean out and go BOOM.

Once the car idles, the fuel pressure registers 45psi. Don't know if it goes up or down when the car goes into boost. Revving the motor in the driveway doesn't put the car into boost. Any tips on motoring the pressure gauge in the engine bay while driving???

That doesnt make sense, the length specs on all that stuff never changed... the hose should have been cut to 7.5". Did I cut it too short?

If that hose coming off was the reason for the issues, than putting back on alone wouldnt solve the problem. All that hose does is allow the module to siphon fuel from the drivers side. But the siphon needs return fuel pressure to work... so if starvation made it stop running, it would need fuel added to run again even after the hose was connected in order to build pressure and activate the siphon.

That said, if the car is running and making pressure now, its something else anyway. Its most likely a bad pressure regulator or an internal pressure leak in the fuel pump module (missing oring on regulator delete fitting, cracked housing, bad seal between pump output barb and filter housing inlet), or a bad fuel pump.

The hose isn't too short, I believe its an AN union. The threading on the union is too short and does not bottom out the female end of the new hose.

But you're absolutely correct, it has to be something else. The problem still persists. The shop that installed the fuel pump hasn't been known to do a good job so I wouldn't be surprised if it was a cracked housing, missing o-ring, or something stupid.

Regardless, I am inclined to just replace everything. What is the model of the aeromotive fpr? Walbro still the pump to use? I'll start with the big stuff and work my way down.

There must just be a burr on the thread or something, its all compatible stuff, it will fit.

Aeromotive 13109 regulator, Walbro 255 pump (gss342) is good for up to 500-550rwhp depending on many other things. Or you can use an Aeromotive 11142 which is the largest I would recommend for that fuel pump housing.

Before any of it, I would pressure test the fuel pump module but applying roughly 60-75psi of air pressure into the fuel pump module outlet, and this would allow you to check for leaks around the regulator delete or the fuel pump output barb, or cracked housing etc.

Ended up being a ripped O-ring in the regulator bypass, now the car runs rich.

Was it the smaller or larger o-ring?

Wow great stuff man thnx for posting.

both :(