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Trouble Starting and Trouble Driving

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Old Oct 30, 2004 | 11:52 AM
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From: san diego CA
Trouble Starting and Trouble Driving

It takes me 2-4 attempts to get my engine started correctly, almost as if it is not getting fuel (thats my guess) and sometimes while I am driving down the road it acts like its going to die from not getting fuel (also just a guess at whats happening).

On monday I am going to replace the fuel pump relay, but I was wondering if anyone else has guesses or opinions on what it may be. Fuel pump possibly?

1986 Trans Am TPI 5.0
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Old Oct 30, 2004 | 01:07 PM
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From: Browns Town
Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
Engine: 406 Hyd Roller 236/242
Transmission: 700R4 HomeBrew, 2.4K stall
Axle/Gears: 3:73 Posi, 7.5 Soon to break
Do a pressure check first to see if it is a fuel problem.
Could be the filter, the regulator or the electrical connections at the pump. I'd hate to see you change the pump and have the same problem.
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Old Oct 30, 2004 | 05:18 PM
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From: san diego CA
Originally posted by JP86SS
Do a pressure check first to see if it is a fuel problem.
Could be the filter, the regulator or the electrical connections at the pump. I'd hate to see you change the pump and have the same problem.
I changed the fuel filter yesterday, but shortly afterwards I got the symptoms I described while driving and my check engine light came on.

I plan on checking the fuel pump relay on Monday.

How do I check the regulator?

Yes, I would hate to change the fuel pump when it is not neccesary as well. BTW, are the fuel pumps in the tank or are they external?
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Old Oct 30, 2004 | 07:05 PM
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From: Browns Town
Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
Engine: 406 Hyd Roller 236/242
Transmission: 700R4 HomeBrew, 2.4K stall
Axle/Gears: 3:73 Posi, 7.5 Soon to break
You need to find out what code the ECM is throwing at that time.
The fuel problem may not be fuel related but a result of another type of failure. If you loose your EST (distributor) pulse because of a failing module, the fuel relay may shut off if the oil pressure switch is not functioning.
It makes sense if your having trouble starting that the fuel pump relay could be bad. The oil pressure switch will bring the pump on but only after oil pressure is built up. If the connection on the switch (or the switch itself) is now starting to go, it could be the whole cause of your stalling.

The pump is going to be in the tank (pretty sure if its an OEM one) which means it will be some work do do the change and if your not real sure...
Put a wire between A & B in the ALDL then turn the key on but don't start it and see what code number flashes. Code 12 is normal with the terminals jumpered and the engine not started.
The code that flashes after that should give some indication of what to look for. Start from there or if you can't find what the code is or what it relates to, ask here and myself or someone can help you from there.
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Old Nov 1, 2004 | 02:27 PM
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From: san diego CA
Originally posted by JP86SS
You need to find out what code the ECM is throwing at that time.
The fuel problem may not be fuel related but a result of another type of failure. If you loose your EST (distributor) pulse because of a failing module, the fuel relay may shut off if the oil pressure switch is not functioning.
It makes sense if your having trouble starting that the fuel pump relay could be bad. The oil pressure switch will bring the pump on but only after oil pressure is built up. If the connection on the switch (or the switch itself) is now starting to go, it could be the whole cause of your stalling.

The pump is going to be in the tank (pretty sure if its an OEM one) which means it will be some work do do the change and if your not real sure...
Put a wire between A & B in the ALDL then turn the key on but don't start it and see what code number flashes. Code 12 is normal with the terminals jumpered and the engine not started.
The code that flashes after that should give some indication of what to look for. Start from there or if you can't find what the code is or what it relates to, ask here and myself or someone can help you from there.
Since you seem to have been following this thread for a few posts, I thought I would update you and take in any feedback you may have.

This morning I disconnected the battery to clear the computer codes, and I also thought I would check out my fuel pump relay. Well, as it turns out, the bracket which holds the relay to the body seems to have broken, and now it is dangling around, rather than being fastened snug to the body.

My theory is that this may have been giving me some problems as it might have banged around when driving down the road. So I have set out to replace the bracket and install a new relay as well as the old one may be damaged.

Do you have any advice on where to get a new/used bracket for my car?
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Old Nov 1, 2004 | 06:58 PM
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From: Browns Town
Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
Engine: 406 Hyd Roller 236/242
Transmission: 700R4 HomeBrew, 2.4K stall
Axle/Gears: 3:73 Posi, 7.5 Soon to break
A good nylon zippy-tie works good.
Drill a hole on each side of the relay and wrap the tie through the holes and around the relay. Pull it tight from the back and it hides the end as well.
Otherwise, it probably to the boneyard to scrounge one.
Jp
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