vrracing

iTrader: (1)

I got around to trying ReTED's next suggestion, test the fuel pressure. We might be on to something...


We did the depressurization procedure and as soon as I pulled the pump connector the car died. That seemed sudden based on the book so we plugged it back in an rev'd it to 3k, pulled the plug and it died.

I cut the line coming from the fuel filter, had my safety glasses on and a towel underneath ready for the flood of high pressure fuel to come squirting out. Nothing. It was a little more than damp.

Odd. I had expected the same thing when I disconnected the fuel lines on the NA when we pulled it, but the line was empty. I assumed that meant the injectors were leaking on the NA and they had drained the line. Which conflicted with the fact that the NA consistently started after 2 or 3 seconds.

So I put the tee in the in-line between the fuel filter and the hardline. Did the yellow jumper.

With the key to On we got 42 psi. Then you're supposed to turn it off and after 5 minutes there should still be 18 psi. We were at zero in certainly less than 90 and probably more like 60 seconds.

So, the books says there is a leak. It's not leaking from any of the hoses and there is no fuel leaking on the floor. And we dont smell gas.

So, what to do next? I think the obvious candidates are:

• Replace the fuel pump - Have a new Walbro ready to go
• Pull the injectors - they were cleaned but could they be jammed with debris?
• Do something with the FPR - there is a procedure to test it but I haven't read it yet.

Advice?

thanks,

Jim

[/LIST]

arghx

iTrader: (3)

this is a stock FPR?

sharingan 19

iTrader: (16)

I had a leak that gave me similar problems, and it was hard to find since there was no puddles, fuel smell, or dripping fuel.

Turned out the rubber hose running from the fuel pump to the hard line had ruptured and it was leaking inside the fuel tank.

vrracing

iTrader: (1)

Arghx - Yes, stock FPR (it's a JDM S5 Tii so everything is by definition suspect).

Shar - Interesting. I assume you mean the lines at the fuel tank. Everything back there was clean and dry (and dusty so when I say "dry" I'm not kidding. We pulled the plate for the depressurization procedure.

I'm thinking we'll start with the pump. I have it and have to install it eventually anyways.

HAILERS2

Duh. The fuel pump has a CHECK VALVE in it to maintain pressure in the fuel rail. See local FSM.

I'd fully expect the engine to die when the fuel pumps plug is disconnected. Pretty darn soon after disconnect.

The fuel pumps check valve seems to be held open by something. Dirt? Or simply the hose clamps on the pump itself are loose, missing, cracked, too large etc.

vrracing

iTrader: (1)

would a failed check valve result in dying at idle and not being able to rev? Does the na make fewer demands on the pump and specifically the value of the check valve than the Tii so that the car would be drivable with the na and then go to **** when you drop in the Tii?

vrracing

iTrader: (1)

Got the Walbro in and it's better. It isnt good, but its better. It still wont idle (green pin jumped or not). It just dies. I can keep it running from 1500-1800 and it pulsates between those two numbers. It will rev now where it wouldnt before.

Since I haven't been able to get an idle, I haven't been able to check the timing with the light with the car running. I stabbed in the NA's CAS (everything on a JDM Tii is suspect) and used a sharpie to mark on top so it was easier to stab. Then I took all but the L1 plug out and hooked my timing light to a second battery and was able to check it with the light that way. The timing is right on.

I rechecked the TPS with the two LEDs. Ignition on but no foot on accelerator and one light, touch the accelerator and no lights. So that's good.

We bought the stuff to build the system pressurizing uber leak detector. The kid will build the TMIC bypass tomorrow and we'll pressurize it tomorrow night. We got a gallon of bubble juice so that should just barely be enough. If there is a leak, we'll find it.

If that finds nothing, I'm thinking either I've screwed up some of the vacuum (or air bleed lines since I know if you get the 3 on the back of the UIM wrong you get bad things happening) or we have something amok in the fuel system since we have spark with good timing, an accurate TPS and fuel pressure (haven't checked it since the Walbro though). So this weekend we'll remove the UIM, TB, etc and tear it all down and build it all back up.

Oh joy!

HAILERS2

Even a non turbo fuel pump is good enough as long as you don't boost. Been there, done that.

A check valve in the pump leaking shouldn't keep the car from idling and driving out of boost. I've more or less messed with that by drilling a 1/16 hole in the fuel pump feed line (metal one on the pump) and driven numerous miles. Since doing that, somewhere I'd read a thread/article/whatever mentioning static electricity being caused by doing this and it's not a safe thing to do. I'm mulling that over.

vrracing

iTrader: (1)

Thanks, Hailer. I went ahead and installed the Walbro. It's better but it aint right yet. I built a TMIC bypass and fit a stopper to the AFM as noted in this thread.

So now I'm off on chasing vacuum leaks.