Fuel in the plenum?
07-17-2014, 11:13 PM
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Car: 87 Trans Am, 99 WS6, 16 Mustang GT
Engine: LB9, LS1
Transmission: 700R4, T56
Axle/Gears: 3.42 Posi, 4.10 Posi
Fuel in the plenum?
I was doing injectors and regulator swap on my friends IROC the other day. His car has been running crazy rich for the past 2 weeks, practically tripping over itself. I told him not to drive the car, but you can probably guess how that went. So the oil was completely saturated with fuel.
Anyway, so I got around to doing the work, and when I took the plenum off, to my surprise, a good amount of fuel poured out of it. How can this happen? the injector is right before the valve, how the fuel made it up there is a mystery to me. The only thing I can think of is through the PCV.
Doesn't really matter now, I'm just curious as to why it happened.
Anyway, so I got around to doing the work, and when I took the plenum off, to my surprise, a good amount of fuel poured out of it. How can this happen? the injector is right before the valve, how the fuel made it up there is a mystery to me. The only thing I can think of is through the PCV.
Doesn't really matter now, I'm just curious as to why it happened.
07-17-2014, 11:15 PM
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Fuel in the plenum?
Fuel PSI regulator diaphragm is bad.
07-17-2014, 11:24 PM
#3
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Car: 87 Trans Am, 99 WS6, 16 Mustang GT
Engine: LB9, LS1
Transmission: 700R4, T56
Axle/Gears: 3.42 Posi, 4.10 Posi
Re: Fuel in the plenum?
Yeah it was old and cracked when I took it out. The previous owner had the entire upper end of the motor apart, new upper and lower intake gaskets, painted the crappy original injectors, etc. Have no idea why he didn't replace the diaphragm while he was in that far.
Everything is back together, like I said, just wondering how fuel got up to the plenum.
Everything is back together, like I said, just wondering how fuel got up to the plenum.
07-18-2014, 07:50 AM
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Car: check
Engine: check
Transmission: check
Re: Fuel in the plenum?
As TTOP350 posted through the FPR vacuum line is common. The other is through the CCP system. Swap the return and vent lines at the tank and the CCP canister fills with fuel.
RBob.
RBob.
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