454 tbi problems
#1
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Car: 1992 Z28 Conv.
Engine: 305 TPI
Transmission: 700r4
Axle/Gears: 10 bolt, 2.73 posi
454 tbi problems
Hey guys my 1990 454ss is starting to **** me off. The truck runs like crap at part throttle and stutters an WOT. So far I've replaced the coil twice, dizzy, plugs, wires, knock sensor, and O2. And the problem is still there and seems to be getting worse. Anything else I should look at? I have a pressure gage and adapter on the way so I can check fuel pressure. Truck is all stock with the exception of no cat, and the timing is set at 6 deg btdc.
Thanks
Mark
Thanks
Mark
#2
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Car: '91 Chevy 1500
Engine: 350
Transmission: 700R4
Axle/Gears: 3.73
Re: 454 tbi problems
Make sure the timing is what it's supposed to be, otherwise it throws off the timing in every table (unless you are custom tuning your chip).
Otherwise, deffinitely check the fuel pressure.
Otherwise, deffinitely check the fuel pressure.
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Car: 1993 Z-71 pickup
Engine: Heavily modified 355 on TBI
Transmission: Had a 4L60e. Now a 700R4
Axle/Gears: Bone Stock
Re: 454 tbi problems
Get your FP guage and go from there. It could be a clogged filter or a failing pump.Once you hook your guage up you'll know.
#5
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Car: 1992 Z28 Conv.
Engine: 305 TPI
Transmission: 700r4
Axle/Gears: 10 bolt, 2.73 posi
Re: 454 tbi problems
Truck only has 7 psi of fuel pressure. Not good huh?? Should be around 13 right? Where should I start the regulator or the pump? The filter is only a few months old.
Thanks
Mark
Thanks
Mark
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Car: 75 Beast
Engine: 383 +EBL Flash
Transmission: 700R4
Axle/Gears: 4.11 with 33"
Re: 454 tbi problems
Perform a dead head test - pinch off the return line, while observing fuel pressure. If it zooms past 20 PSI FP is probably OK if it stays around 7 PSI, you have a tired FP, or fuel sock, or clogged in line filter or ruptured in tank hose.
//RF
//RF
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Car: 84' Monte
Engine: 350
Transmission: 700-r4
Axle/Gears: ferd 9" posi 3.50 gears
Re: 454 tbi problems
Regulators rarely fail by just loosing pressure. If they fail, which is rare, they rupture the diaphram and leak. Your pump is dead......
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