Fuel sending unit
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From: Compound in the Grove, Ga.
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St. Jude Donor '16
The FP and sending unit are an assembly although the pump is replaceable. The float/rheostat portion sends the fuel level to the dash gauge. Over time the small line connecting the pump to the hard line in the tank will swell and get lose or the plastic clamp come apart, resulting in pressure loss.
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Instructor
Joined: Nov 2012
Posts: 214
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From: Long Island
The FP and sending unit are an assembly although the pump is replaceable. The float/rheostat portion sends the fuel level to the dash gauge. Over time the small line connecting the pump to the hard line in the tank will swell and get lose or the plastic clamp come apart, resulting in pressure loss.
Melting Slicks
Joined: Oct 2000
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From: N.E. WA
Race Director
Joined: Feb 2002
Posts: 11,616
Likes: 1,055
From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
2025 C4 of the Year Winner - Unmodified
2024 C4 of the Year Finalist - Unmodified
2020 C3 of the Year Finalist - Unmodified
2019 C4 of Year Finalist (performance mods)
2018 C4 of Year Finalist
2015 C4 of the Year Finalist
St. Jude Donor '16
What year? Did you replace the fuel filter? What FP are getting?
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Instructor
Joined: Nov 2012
Posts: 214
Likes: 8
From: Long Island
94 6spd. Pressure is 38 key on engine off vacuum line on. Filter is new. Pump is new, double checked the fuel line in place of the pulsator, its tight. Put in a second new regulator. It's good. Original injectors are not leaking. Been chasing this for a while, I'm at a loss.
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Instructor
Joined: Nov 2012
Posts: 214
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From: Long Island
Lt fuel trim cl 16
Lt fuel trim l 149
Lt fuel trim r 139
Evap duty(%) 0
Evap solenoid off
Cyl ID 86
Rpm 750
Egr duty (%) 0
ks counter 1951
Fc1 relay off
Fc2 relay off
Iac position 11
Inj l pw(ms) 3
Inj r pw (ms) 3
Knock ret 0
Knock sensor 1951
Closed loop
Maf (gr/s) 7
Map ("hg) 9.81
Iat (f) 119
02 sensors fluctuate and are new
Tps sensor .71
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Joined: Feb 2002
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From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
2025 C4 of the Year Winner - Unmodified
2024 C4 of the Year Finalist - Unmodified
2020 C3 of the Year Finalist - Unmodified
2019 C4 of Year Finalist (performance mods)
2018 C4 of Year Finalist
2015 C4 of the Year Finalist
St. Jude Donor '16
Not positive about the LT1 but I think at idle air off TPS should be .23v-.59v.
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