Fuel Problem
Thread Starter
Instructor
Joined: Oct 2003
Posts: 117
Likes: 0
From: Coweta OK
Fuel Problem
Well my car is still not running. It starts and dies. Acts just like it runs out of gas. I put on a new fuel filter. I don't have a fuel pressure testor but pump is running. If I turn the key off and let the car set for second, then turn the key on and let the pump run the car starts right up, then dies like it runs out of gas. Could it be the pressure regulator? If so, where is it on my 86? I have not been able to drive it for a week and its killing me.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Fuel Problem (VettBrat)
Since the fuel rail gets primed enough to start the engine the fuel pump relay and fuel pump should be ok.
It sounds like the oil pressure switch is faulty as this is the only source of power to the fuel pump after the fuel line has been primed.
To verify this, jumper +12 Vdc to ALDL pin G (lower left) and start the engine; if the engine runs ok, replace the oil pressure switch. Or you could simply clip a jumper across the oil pressure switch pins (see wire description below) and start the enine.
There are two oil pressure switches on the stalk that sits left of the dist in the rear rail of the engine block. The switch you want to replace has (at least on my '88) an Orn & Red wire.
It sounds like the oil pressure switch is faulty as this is the only source of power to the fuel pump after the fuel line has been primed.
To verify this, jumper +12 Vdc to ALDL pin G (lower left) and start the engine; if the engine runs ok, replace the oil pressure switch. Or you could simply clip a jumper across the oil pressure switch pins (see wire description below) and start the enine.
There are two oil pressure switches on the stalk that sits left of the dist in the rear rail of the engine block. The switch you want to replace has (at least on my '88) an Orn & Red wire.
Thread Starter
Instructor
Joined: Oct 2003
Posts: 117
Likes: 0
From: Coweta OK
Re: Fuel Problem (65Z01)
"jumper +12 Vdc to ALDL pin G (lower left)"
I understand the ALDL pin part of that but not the +12 Vdc. Are you saying run a hot wire from the battery to the ALDL pin? Maybe just typed myself into an answer, LOL.
I understand the ALDL pin part of that but not the +12 Vdc. Are you saying run a hot wire from the battery to the ALDL pin? Maybe just typed myself into an answer, LOL.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Re: Fuel Problem (65Z01)
That's not quite right. The pump should run from the ECM signal, through the relay, while the engine is running. The oil pressure switch is wired parallel to the relay and provides a back up, in case of relay failure.
On the discribed, "stalk" there are two devices. The large can with a single wire is the oil pressure guage sending unit. The smaller item with two wires is the oil pressure switch.
Jumping pins "A" to "G" on the ALDL runs the pump, too. This does little but prove that the pump and fuse are OK.
I think it's time to invest in a fuel pressure guage and do some trouble shooting. Good luck, and...
RACE ON!!!
On the discribed, "stalk" there are two devices. The large can with a single wire is the oil pressure guage sending unit. The smaller item with two wires is the oil pressure switch.
Jumping pins "A" to "G" on the ALDL runs the pump, too. This does little but prove that the pump and fuse are OK.
I think it's time to invest in a fuel pressure guage and do some trouble shooting. Good luck, and...
RACE ON!!!
Burning Brakes
Joined: Feb 2000
Posts: 824
Likes: 2
From: Camden SC
Re: Fuel Problem (Bruthish)
You really need a fuel pressure gauge. If you suspect a fuel problem, you need to keep track of what the fuel pressure is doing. It is possible to have enough pressure to start but insufficient volume to keep running. This usually shows up under load however with the car running, then car dying, a rapid drop off in pressure will send us to the troubleshooting diagram and will confirm a fuel problem. If you are planning on keeping this car and performing troubleshooting/repairs on fuel injected engines, the fuel pressure gauge is a near must. Or, swag (scientific wild a** guess) and start buying parts. Happens every day. Been there done that.
About $45 at Sears will buy the Actron Fuel Pressure Tester, you will be able to perform both a flow volume check and pressure check.
Changing the filter was a very good idea. Never hurts.
Good luck with this repair.
[Modified by dlmeyers, 7:32 PM 1/30/2004]
About $45 at Sears will buy the Actron Fuel Pressure Tester, you will be able to perform both a flow volume check and pressure check.
Changing the filter was a very good idea. Never hurts.
Good luck with this repair.
[Modified by dlmeyers, 7:32 PM 1/30/2004]
