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fuel pump problem

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Old Apr 19, 2009 | 07:48 PM
  #1  
noroxus's Avatar
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From: Union Beach, NJ
Car: 1984 Z28
Engine: 360ci SBC
Transmission: WC T5
Axle/Gears: 9 bolt 3.27 Posi
fuel pump problem

My friends camaros (88 5.0 tbi) fuel pump wont do anything until the oil pressure comes up.

is there any easy fix to this?
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Old Apr 19, 2009 | 08:55 PM
  #2  
5678TA's Avatar
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From: Maui, Hawaii
Car: 1984 Trans Am
Engine: broken 385sbc
Transmission: G-Force rebuilt T-5
Axle/Gears: Currie 9" Ford 4.30:1
Re: fuel pump problem

fuel pump relay?? my truck has tbi and the pump will go on if there is oil pressure..(ex: after its shut down and bleeding oil pressure off it stays on) only other thing that gives power is the relay. change that and see what happens.
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Old Apr 19, 2009 | 09:37 PM
  #3  
noroxus's Avatar
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From: Union Beach, NJ
Car: 1984 Z28
Engine: 360ci SBC
Transmission: WC T5
Axle/Gears: 9 bolt 3.27 Posi
Re: fuel pump problem

Originally Posted by 5678TA
fuel pump relay?? my truck has tbi and the pump will go on if there is oil pressure..(ex: after its shut down and bleeding oil pressure off it stays on) only other thing that gives power is the relay. change that and see what happens.
I never worked on it myself, but her father (mostly auto inclined) worked on it and that didn't work, but knowing that family, he probably changed another relay in that little cluster.

i'm not entirely sure which relay it would be in that corner, have any pics?
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Old Apr 19, 2009 | 10:16 PM
  #4  
5678TA's Avatar
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From: Maui, Hawaii
Car: 1984 Trans Am
Engine: broken 385sbc
Transmission: G-Force rebuilt T-5
Axle/Gears: Currie 9" Ford 4.30:1
Re: fuel pump problem

cant say for sure since i ripped out my entire wiring harness when i built my car. and i didnt have TBI. but you should be able to find out which one in a repair manual.

but on my truck, there are two relays side by side. one for fuel pump and the other for AC. they should be the same type so just swap the plugs: fuel pump plug to AC relay and AC plug to fuel pump relay. if it still doesnt work, try turning on the AC to completely rule out the relay. if it works, relay is good and problem is elsewhere. most likely the hot lead from the ignition to the fuel pump relay.
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Old Apr 20, 2009 | 10:31 AM
  #5  
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Car: '91 Z28 convertible
Engine: TPI
Transmission: T5
Axle/Gears: 3.27 posi disc
Re: fuel pump problem

Originally Posted by noroxus
i'm not entirely sure which relay it would be in that corner, have any pics?
They all look alike. (yeah, go ahead and call me a racist :roflmao: )

The best way to identify the relay is by the wires. The fuel pump relay will have a thick red wire, thick orange wire, thick tan/white wire, thin black wire, think green/white wire.

When he turns the key, he should feel/hear the relay click for 2 seconds and hear the pump prime. If there is no click, the relay/wiring is likely bad. If he hears the click but no fuel pump, it's likely wiring.

He can try this short troubleshooting article: http://www.austinthirdgen.org/index.php?pid=35

Hope this helps.
Lou
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Old Apr 22, 2009 | 11:29 PM
  #6  
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From: close to Wichita Kansas
Car: '91 RS CP now is the son's driver
Engine: CP =3.1, will get V-8 maybe someday
Transmission: stock
Axle/Gears: 3.42 posi W/ disks
Re: fuel pump problem

the ECM is suposed to turn on the fuel pump for 30 seconds after key on, if you are not getting this I would say you need a replacement ECM
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Old Apr 23, 2009 | 08:52 AM
  #7  
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Car: '91 Z28 convertible
Engine: TPI
Transmission: T5
Axle/Gears: 3.27 posi disc
Re: fuel pump problem

Originally Posted by macertheracer
the ECM is suposed to turn on the fuel pump for 30 seconds after key on, if you are not getting this I would say you need a replacement ECM
Just to clarify, the fuel pump prime pulse is 2 seconds.
If the fuel pump doesn't prime, it's not necessarily automatically a bad ECM, it can be a bad relay, bad wire, blown fuse or more. It's better to find the faulty component before wasting lots of money on a new ECM.

Hope this helps.
Lou
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