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Old Mar 19, 2016 | 06:59 AM
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Default Injector testing

I have Holley 120 injectors, recently a problem came up where my tune changed, more on startup and restart-it feels like a carb that's flooding, you have to floor it to clean it out-I beat my head against the wall messing with the tune, now I am suspecting maybe an injector-my sons truck bent a rod when one stayed open, so I am a little gun shy now, lol
Anyway, how would you test the injectors-the gauge is in the fuel rails, but it leaks down, prob thru the filter or return
The car seems fine driving, builds boost, maintains AFR's as set
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Old Mar 19, 2016 | 07:17 AM
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Originally Posted by forcd ind
I have Holley 120 injectors, recently a problem came up where my tune changed, more on startup and restart-it feels like a carb that's flooding, you have to floor it to clean it out-I beat my head against the wall messing with the tune, now I am suspecting maybe an injector-my sons truck bent a rod when one stayed open, so I am a little gun shy now, lol
Anyway, how would you test the injectors-the gauge is in the fuel rails, but it leaks down, prob thru the filter or return
The car seems fine driving, builds boost, maintains AFR's as set
My pressure leaks down too not sure why though. But I got my injectors tested by a guy on YB - I think his name was Eric Derr??? Very reasonable and priced right.
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Old Mar 19, 2016 | 01:40 PM
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Well I tried to test, kind of a dumb move, lol
I go thru one fuel rail, cross over to the other, then out to the reg and return.
I disc the line to the reg, plugged it, fig. I would turn on the pump, hit the fuel cutoff back by the tank, then kill the pump-well, I wasn't thinking about fuel pres.
so of course w/o the reg in the system, it pegged the 100 psi gauge, so the injectors got full pressure-I watched the pressure drop slowly, not sure why, fig it was thru the injectors, but maybe not-anyway, I hooked it all back up, spun the engine over by hand incase a cyl filled, then fired it up-fired right up w/o touching the throttle, warmed up and did a couple restarts, all seems normal-if I had a leaky inj. I think for sure with over 100 psi sitting on them it would have started rich-maybe it just needed tweaking
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Old Mar 19, 2016 | 03:47 PM
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Originally Posted by forcd ind
Well I tried to test, kind of a dumb move, lol
I go thru one fuel rail, cross over to the other, then out to the reg and return.
I disc the line to the reg, plugged it, fig. I would turn on the pump, hit the fuel cutoff back by the tank, then kill the pump-well, I wasn't thinking about fuel pres.
so of course w/o the reg in the system, it pegged the 100 psi gauge, so the injectors got full pressure-I watched the pressure drop slowly, not sure why, fig it was thru the injectors, but maybe not-anyway, I hooked it all back up, spun the engine over by hand incase a cyl filled, then fired it up-fired right up w/o touching the throttle, warmed up and did a couple restarts, all seems normal-if I had a leaky inj. I think for sure with over 100 psi sitting on them it would have started rich-maybe it just needed tweaking
100 psi reset! Lol. Hope it's fixed.
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