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Discussion Starter · #1 ·
I recently bought an 87 alfa spider veloce that had been sitting for over a year. I emptied and cleaned the gas tank of rotten fuel, and installed a new main fuel pump and fuel pump relay. There is juice going to the in-tank pump, but no sign of activity. The wires going to the main pump underneath show no signs of life. When i pour fuel into the carbs directly, the car starts and runs beautifully for a short bit, then cuts out. So i know it will start, and sounds great. I just can't seem to get the new main pump to work. Please help. I've owned and worked on more than 50 classic cars in my time, but this little problem has me baffled. Thanks in advance for any help.
 

· But Mad North-Northwest
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An '87 should have had electronic fuel injection, so yours has obviously been converted to carbs. What that means is that God only knows how they hooked up the fuel pumps. I suspect you'll just need to trace the wires and see why you're not getting power at the main pump. Worst case run a new fuel pump power wire.

The in-tank pumps are notorious for failure, so if it's getting 12V and has a good ground and still not running it may just be toast. Note that there is supposed to be a filter sock over the inlet for this filter, and if it's not in place the pump will probably get killed by junk in the tank.
 

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Discussion Starter · #3 ·
fuel pump power

An '87 should have had electronic fuel injection, so yours has obviously been converted to carbs. What that means is that God only knows how they hooked up the fuel pumps. I suspect you'll just need to trace the wires and see why you're not getting power at the main pump. Worst case run a new fuel pump power wire.

The in-tank pumps are notorious for failure, so if it's getting 12V and has a good ground and still not running it may just be toast. Note that there is supposed to be a filter sock over the inlet for this filter, and if it's not in place the pump will probably get killed by junk in the tank.
Thanks for the fast replay. I apologize-- i miss spoke with my initial statement. The car is stock, and clean, and does not have carbs. I shot some fuel into what i believe is called the plenum chamber, and it ran for a little bit. Still, no electric juice at main pump. thanks
 

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Discussion Starter · #5 ·
Check the fuse.

There's also a relay that controls the fuel pump and it has a reputation for causing trouble now and then. Do a search under "fuel pump relay."

Here's one thread:

http://www.alfabb.com/bb/forums/spider-1966-up/209029-1989-spider-dies-immediately-update.html

Here's another good site:

Bosch L-jetronic Fuel Injection Idle Adjustment Diagnostic and Tune Up Technical Article Alfa Romeo Spider Specific

Thanks-- i have replaced the relay with a new one, as well as the fuse. There may be some problem with the wiring which looks a little different than what I've been seeing in all the photos here.
 

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Discussion Starter · #9 ·
Help PLEASE

I hope I'm following the right thread and all that. Here's where I stand-- 87 Alfa Spider. New battery, new in-tank fuel pump, new underneath fuel pump, new fuel pump relay, new fuel filter, new fuse in line.

When I have shot some fuel into the plenum? (I don't know whether this is right or wrong to do), the car runs and sounds great for about 15 seconds. The in-tank pump hums when i turn the key but there is no power to the underneath fuel pump. All I have to test is a little test light, which works everywhere else but not at the main fuel pump. There is current to the fuel pump fuse, but none to the main pump. When I ran a hot wire to the pump, it worked fine, but made rather dangerous looking sparks.

The only thing left to change, as far as I can see, is a main relay, or the computer unit itself. I seem to be so close, and yet so far. Am I missing something? Is there any alternative way to get the main pump running?

PLEASE-- any help or advice would be greatly appreciated.:(
 

· Trained (ex)Professional, , 1953-2018 RIP
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The in-tank pump hums when i turn the key but there is no power to the underneath fuel pump.
The fuelpump power supply is designed such that the pumps receive power ONLY when the engine is cranking or the engine is running. If your in-tank pump is running with the key in the on position and engine off, somethings wrong. To test the circuit to the main pump, remove the fuelpump relay and jump terminals 30 and 87 in the relay socket. Does the fuelpump run or is there power to it?
 

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Discussion Starter · #12 ·
Fuel pump power

Thanks for the help. I jumped terminals 30 and 87 as you suggested, and the in-tank fuel pump went on. I still don't know if there is power going to the main fuel pump, but I want to double check to see if the in-tank pump is in fact pumping, and then have someone crank the car and see if i have juice to the main pump. I'm hopeful that I'm getting close. Again, thanks so much,
 

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If I remember correctly, both the tank pump and main pump are feed by the same wire. With the relay jumpered take your test light and put one end to some bare metal of the body and the other end to either terminal on the pump. Your light should glow on one or both. If it glows on both I would bet you have lost the ground connection to the pump. If it doesn't light on either, follow the wire from the main pump to the tank pump and look for a junction that might be unplugged. If you find that you actually do have power to the main pump and the ground connection is good but the pump doesn't run, then it's time for a new pump. This would also be a good time to get the tank cleaned out and replace all the rubber fuel lines.

Dick Stachowiak
 

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Discussion Starter · #14 ·
The fuelpump power supply is designed such that the pumps receive power ONLY when the engine is cranking or the engine is running. If your in-tank pump is running with the key in the on position and engine off, somethings wrong. To test the circuit to the main pump, remove the fuelpump relay and jump terminals 30 and 87 in the relay socket. Does the fuelpump run or is there power to it?
When I connect these terminals, the in-tank pump goes on and makes noise, but still no power to the main pump below. As I mentioned in my initial post, i have installed new pumps, new battery, new fuses, and a new fuel pump relay. When I turn on the key, the in-tank pump makes noise and runs. But, no power to the main pump underneath.
 
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