Hi, here's the deal.
i rebuilt my engine, nothing fancy. I cleaned and flow tested stock injectors, they all are 100% ok. Stock turbo, port and polished intake and exhaust. STG Ultimate chip set on T1-16, 3-bar map. No muffler just a high flow cat. Timing is ok, plugs clean (NGK Iridium). Adfpr, tested today, works ok.
I don't have a f/p gauge but going to order one today, i know that is the first thing to check, but i thought maybe someone else have had a simular problem?
I installed STG and turned f/p up to 50psi (base value), truck runs really good all the time except at wot, you go wot and when it starts to build close to 15psi boost, it starts to miss fire and die when you let of the throttle. Restart right away but runs kind of rough until you hit the gas a couple of times. Must be a fuel problem, so i turned the f/p done to 38psi. Problem solved, no more missfire, but at wot you can hear on the exhaust that it's not running right, like it's running lean? (I haven't data logged it yet, due to that i haven't had time yet. )
So i thought ok the fuel pump is bad, today i installed a Walbro 255 HP and rewire the pump straight to the battery. Turned pressure to 50 psi (base) problem still there. Turn pressure down to 40, truck runs great except the exhaust sound like it's running lean? (egt on wot is 1400 @ #1 cylinder really close to head)
This is driving me crazy, i got a new fuel filter by the way.
My though of this is that i have a restriction in the fuel line, maybe it got bent and kinked when i r&r the engine? I also checked today that the fpr increased the pressure with boost, and it's working ok. Could a restricted fuel line cause this problem, shoulden't the problem be there what ever f/p you are running?
I'm getting tired of this truck, got this new engine and can't run it at the track :evil:
i rebuilt my engine, nothing fancy. I cleaned and flow tested stock injectors, they all are 100% ok. Stock turbo, port and polished intake and exhaust. STG Ultimate chip set on T1-16, 3-bar map. No muffler just a high flow cat. Timing is ok, plugs clean (NGK Iridium). Adfpr, tested today, works ok.
I don't have a f/p gauge but going to order one today, i know that is the first thing to check, but i thought maybe someone else have had a simular problem?
I installed STG and turned f/p up to 50psi (base value), truck runs really good all the time except at wot, you go wot and when it starts to build close to 15psi boost, it starts to miss fire and die when you let of the throttle. Restart right away but runs kind of rough until you hit the gas a couple of times. Must be a fuel problem, so i turned the f/p done to 38psi. Problem solved, no more missfire, but at wot you can hear on the exhaust that it's not running right, like it's running lean? (I haven't data logged it yet, due to that i haven't had time yet. )
So i thought ok the fuel pump is bad, today i installed a Walbro 255 HP and rewire the pump straight to the battery. Turned pressure to 50 psi (base) problem still there. Turn pressure down to 40, truck runs great except the exhaust sound like it's running lean? (egt on wot is 1400 @ #1 cylinder really close to head)
This is driving me crazy, i got a new fuel filter by the way.
My though of this is that i have a restriction in the fuel line, maybe it got bent and kinked when i r&r the engine? I also checked today that the fpr increased the pressure with boost, and it's working ok. Could a restricted fuel line cause this problem, shoulden't the problem be there what ever f/p you are running?
I'm getting tired of this truck, got this new engine and can't run it at the track :evil:
