Intermittent engine stall, Need help interpreting powerlogger

[wcash]

Hi all. Engine ran fine around town this past weekend.  I shut it down and tried to crank it up about 30 minutes later and the motor starts but stalls out almost immediately.  I let the car sit a couple of days and started it up today after a couple of tries.  Scanmaster showing some odd readings, the AF jumping up to 19.99 from the usual 14 to 15 and the green light on the board in the kick panel coming on and off.  Turned the ignition off and back on and saw the AF go back down to normal.  Started the car and drove fine but after a couple of minutes the engine died.  I got it started again before coasting to a stop, ran good for a couple of minutes then repeated stall.  Kept this up till I got her back home.  I've attached some Powerlogger logs from various dates.  The 3-29-16 log was recorded today after I got back home and tried to restart the car. 

I'm hoping someone can review the logs and help me determine what is going on.  It seems like maybe the board in the kick panel maybe going out?  I had a battery change since the November logs, but I think I entered the settings back in the Powerlogger correctly although initially the settings did not seem to stick and I had to redo a couple of times.  All help is much appreciated.

1987 T-Top Grand National

ENGINE-PARTS
• Stock 92000 mile with new valve springs & new rear main seal @ 72000 miles
• Motorsport black "rough powder coat" look valve covers
• Black powder coat on throttle body/plenum
• RJC deep oil pan & sump, 8 quarts

TRANSMISSION
• Stock PTS shift kit @ 75000 miles
• PTS deep aluminum trans pan, external HD trans cooler, trans temp gauge
• D5 stock converter

INDUCTION/EXHAUST
• TA-49
• BBTSC Boost control (interior controller)
• PowerStroke front mount IC with silver powdercoat pipes
• 62mm throttle body bore/RJC Powerplate
• Stainless Terry Houston downpipe & test pipe-electric dump(interior control)
• Hooker 2.5" dual exhaust with Aerochamber mufflers

FUEL SYSTEM/MANAGEMENT
• Walbro 340
• Adjustable fuel pressure regulator
• Additional fuel pressure gauge off fuel rail on flex hose
• 60lb flow matched injectors
• 6.1 TT chip (LT1 MAF & Translator Plus-inside interior)
• Alky Control methanol injection kit
• Powerlogger & Scanmaster

[TexasT]

How much fuel pressure do you have it set at? Last fuel filter change? Is battery voltage dropping off? I'd be inclined to think it is fuel related. My last tussle involved the tank wiring and corrosion of it.

[Forzfed]

Like Rich said, I would check the filter and then the pump.  If the pump is on it's way out it will run for a while till it gets hot then die.  Let it cool down for a bit and it will fire back up.

[daveismissing]

Disconnecting the logger board from the ECM during the no start phase would clearly eliminate that possibility. I had a GM fuel pump on another newer  car that ran fine when warm but would not start up again till cool. Stopping for gas was a 20 minute exercise.

[Steve Wood]

remove the power logger board and see if it runs okay

[wcash]

Thanks for all the ideas.  I believe it is a fuel issue.  I'm not getting any pressure on my gauge off the fuel rail when I turn on the ignition.  I'm thinking I should get at least 40 before cranking.  Pressure still zero when cranking.  Wiring looks good back to front.  Did not have time to look at the fuel filter, although I think I would get some kind of pressure if the filter was dirty.  Now I'm thinking bad fuse but more than likely the pump went out since it happened intermittently and now won't start at all.  Doesn't this rule out a powerlogger issue?  I did not have time tonight to track down the EMC and unplug the powerlogger.  Would no pressure cause the scanmaster to read out 19.99?  I don't think the powerlogger can shut down the pump!  Is there another way to confirm the pump is out or have I pretty much done it?

[Forzfed]

Try the jumper wire and see if the pump works.  What is your oil pressure like?

[wcash]

Oil pressure at 25 while cranking.  I don't know how to try the jumper wire.  Is that something you can walk me through?

[TexasT]

There is a couple  electrical connections behind the alternator. A black and a green one. The black one does the fuel pump. I keep a jumper in my car to get me home. You can pretty much bypass the relays but if the wiring to the pump isn't working, jumping it wont do any good.

[Steve Wood]

Thanks for all the ideas.  I believe it is a fuel issue.  I'm not getting any pressure on my gauge off the fuel rail when I turn on the ignition.  I'm thinking I should get at least 40 before cranking.  Pressure still zero when cranking.  Wiring looks good back to front.  Did not have time to look at the fuel filter, although I think I would get some kind of pressure if the filter was dirty.  Now I'm thinking bad fuse but more than likely the pump went out since it happened intermittently and now won't start at all.  Doesn't this rule out a powerlogger issue?  I did not have time tonight to track down the EMC and unplug the powerlogger.  Would no pressure cause the scanmaster to read out 19.99?  I don't think the powerlogger can shut down the pump!  Is there another way to confirm the pump is out or have I pretty much done it?

I misread your first post....does not sound like a PL problem at this point.   Fix your fuel problem and it will probably be ok

[wcash]

It was a bad relay under the back bumper near the tank.  Replaced it and back rolling.  Thanks for the support.

[Steve Wood]

Glad it was an easy fix!

[wcash]

Yes.  I was concerned it was the fuel pump and I would have probably farmed out that fix for some serious $.