2001 viper w/ built engine and paxton. Fuel system is double RSI in-tank (2x walbro 267), external Weldon regulator, 80lb bosch injectors. Car was dyno tuned by Torrie ~2yrs ago (HP Tuners + stock ecu) and has run flawlessly since but today decided to "break".
If I try to start the car it cranks, sometimes sputters like it almost wants to start, but will not start.
If I remove the fuses for both fuel pumps, the car will start immediately, idle for a second, then die.
If I then put the fuses back in (either 1 or both pumps), the car will immediately start, idle fine and drive fine. Going WOT runs like a ***** ape and does not blow up. However, when I stop the car and turn it off, when I try to restart it it will not start unless i remove the fuses for the fuel pump, start it, let it die, then plug the fuses back in. It does not matter if, once it starts up, if I drive the car for 5 minutes, idle it for 5 minutes, or quickly turn it back off .... as soon as i key off it will not restart until I first run it briefly with the fuel pumps disconnected.
Regulator shows 56psi with vacuum hoses disconnected (exactly where I set it years ago) when cranking or idling. When I key on the pumps turn on (audible), regulator goes to 56psi, then back to 0 when the pumps shut off 1-2 seconds later.
It almost feels like the manifold/fuel rail is flooded with fuel, but that doesn't make sense because then the car wouldn't idle or drive fine once it starts, and when I can get it to start in that above sequence of events it does so immediately without any issues (e.g., coughing, hesitation, etc.).
edit: I also can't see it being something in the tune because it's been perfectly fine for 2 years, and if the tune were flooding it with fuel on start, then when I plug the fuel pumps back in it would re-flood.
edit 2: If i leave the car sit for ~2hrs it will start up on the first crank and idle fine. If I turn it off and immediately back on, it will go back to just cranking and coughing, until I unplug the fuel pump, let it fire up and idle for a second to clean the rails out, die, then plug the fuel pump back in and it will start up immediately. I suppose a solution is to put the fuel-pump-on wire on an off/on switch and first start the engine with it off then on, but that still leaves me wondering *** is going on
If I try to start the car it cranks, sometimes sputters like it almost wants to start, but will not start.
If I remove the fuses for both fuel pumps, the car will start immediately, idle for a second, then die.
If I then put the fuses back in (either 1 or both pumps), the car will immediately start, idle fine and drive fine. Going WOT runs like a ***** ape and does not blow up. However, when I stop the car and turn it off, when I try to restart it it will not start unless i remove the fuses for the fuel pump, start it, let it die, then plug the fuses back in. It does not matter if, once it starts up, if I drive the car for 5 minutes, idle it for 5 minutes, or quickly turn it back off .... as soon as i key off it will not restart until I first run it briefly with the fuel pumps disconnected.
Regulator shows 56psi with vacuum hoses disconnected (exactly where I set it years ago) when cranking or idling. When I key on the pumps turn on (audible), regulator goes to 56psi, then back to 0 when the pumps shut off 1-2 seconds later.
It almost feels like the manifold/fuel rail is flooded with fuel, but that doesn't make sense because then the car wouldn't idle or drive fine once it starts, and when I can get it to start in that above sequence of events it does so immediately without any issues (e.g., coughing, hesitation, etc.).
edit: I also can't see it being something in the tune because it's been perfectly fine for 2 years, and if the tune were flooding it with fuel on start, then when I plug the fuel pumps back in it would re-flood.
edit 2: If i leave the car sit for ~2hrs it will start up on the first crank and idle fine. If I turn it off and immediately back on, it will go back to just cranking and coughing, until I unplug the fuel pump, let it fire up and idle for a second to clean the rails out, die, then plug the fuel pump back in and it will start up immediately. I suppose a solution is to put the fuel-pump-on wire on an off/on switch and first start the engine with it off then on, but that still leaves me wondering *** is going on
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