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Discussion Starter #1
1988 Spider Quad. 28K miles
Both pumps are humming but there is no gas making it to the injector rail. I disconnected gas line at rail, put it in a soda bottle and got nothing when I tried to start. It'll sputter some times and a couple of times it ran for a minuet or so then stopped.
Bullet fuse under rear shelf has continuity.
I've pulled the in-tank pump and inspected step hose and tested that it does run. I can hear it running (and gurgling) and the main pump sounds like it's working.
In order to do these diagnostics I had to jump #87 to #30 on the main relay under the rear shelf. The smaller pump relay is ok as I had another one to switch out.
The fuel filter has about 300 miles on it
I'm thinking main fuel pump issue which is something I have not fully checked by disconnecting outlet hose and see if gas pumps out. At 72 it's getting more difficult to get out from underneath the car.
I've read all the diagnostic stuff and I'm running out of things to check so, if anyone has any ideas I'd appreciate your reply's.
 

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1988 Spider Quad. 28K miles
Both pumps are humming but there is no gas making it to the injector rail

I'm thinking main fuel pump issue which is something I have not fully checked by disconnecting outlet hose and see if gas pumps out
either blocked hard line or pump is not putting out or
hose from pump is kinked maybe?
evap control system.JPG

72? I can hardly get out from under the car at 62! You're doing very well:)
I still have a fuel filter sitting on the shelf....just thinking about getting under the car (it is really a 10 minute job!) gives me back ache!

One trick I use is to lie on a slippery surface...I use a large flattened out cardboard box....large, about 3 foot long.
 

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Discussion Starter #3
Yup, I've got to get underneath and see if the main pump is really working not just sounds like it's ok.. If is working then I'll have to check further up the line I guess.
 

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Discussion Starter #5
That hurt. Back on subject, I managed to disconnect the pump hose just before the filter and all I get is a dribble. Kind of like me and the old prostrate...slow stream. Ordered a new pump from Vick Auto...they have a special at $67. Then I took a nap. Hope that does it. Let you know.
 

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Discussion Starter #6
Just wanted to add that I've had Alfa's since I was 16 and most had Webers. This is the first Bosch FI I've owned so when something goes wrong...well, I can't sleep at night. How they managed to stuff all those electronics, including the seat belts, in that car is baffling. What a nice ride though. My '59 Spider was so easy to work on but I had to work on it a lot more often

than the Quad.
 

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1973 Spider; the daily
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If your having s hard time getting under the car like me and you can get the car up a good amount I would look at a creeper. There just a bed on wheels.
 

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Discussion Starter #8
Update. Put a new main fuel pump in today and it did not fix the problem. Thought I eliminated all the possibilities but I guess not. Question; the in-tank pump runs but it also gurgles. Is that normal? I'd like to see if it's pumping but I'm a little hesitant because of the gas and electrics so close by. This fuel injection has me baffled. It's any one of a dozen things that's not functioning. Just have to figure out which thing or I'm going to end up with a lot of pricey spares. Any thoughts please!
 

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86 Veloce
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Have you taken the fuel line off at the in side of the rail? Fuel there? From reading your previous posts it sure sounds like a plugged line. Pull all of the lines off the hard lines and blow compressed air through them starting at the tank and work forward. If the flexible lines are 30+ years old they need to be replaced anyway
 

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In tank pump gurgles? How much fuel is in the tank? If a half or less the stepped hose on the in tank pump may be cracked or broken. That'll put more strain on the in tank and main pump causing failure. Have you checked for rust and or other scum in the tank? Your in tank filter could be clogged causing a strain on the in tank pump hence the gurgle. I doubt a clogged line. Mu guess is a clogged filter in tank or a cracked or broken stepped hose. Easy to check and no getting on the ground. While you're in the tank, I'd replace that pump also. It's due, especially if it's original. Just my .02c. Hope this helps.
 

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All good suggestions and possibilities. The fact remains though, if the fuel system is that old the hose needs to be replaced, from the tank to the injector hoses. Many an Alfa have burned to the ground from fuel system fires.
 

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Discussion Starter #13
Haba1492, The step hose was one of my thoughts also. It looks good but I didn't take it apart for a close examination. Will do that. What I don't understand is the car will start sometimes and run for a few seconds then quit. Right now I'm thinking in-tank pump or main ECU relay. Any other thoughts?
 

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Skibum is absolutely correct about replacing the fuel hoses. Especially the fi and csi hoses. Mostly out of a concern of leaking and fire. Kentjw, if there is a bunch of junk in the tank, you can get a few seconds of pressure to allow a start and run. Then the pump sucks enough crap into the filters/pump to clog them. Wait a few minutes, the crap settles down and you can crank it again till the crap again causes a clog. Logically thinking, if you have no fuel to the primary pump, then it's an issue w the in tank system. Either a weak pump, bad stepped hose or crud in the tank clogging the filter and or fouling the pump. I dealt w this issue about 8 months ago on my 86 Quad. 2 new pumps, 2 new filters and a pressure washed tank and it's been good ever since. FYI, if the pumps are running, there is no problem w fuses or relays. It's a straight shot from the tank to fuel rail w only pumps, lines and filters in between. Good luck.
 

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Discussion Starter #15
Had the in-tank pump out and looked in the tank. Just a few specs of whatever which I got out. The cloth filter was changed a few years ago and still looks good. It will run for a few seconds then quit. Where does the gas come from for it to start and stop like this?
 

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What do you mean 'it will run for a few seconds then quit'? The fuel pumps? Or the engine?

The fuel pumps get power only under two conditions. First 1) the engine is running - the drive relay gets a signal via a sense wire at the coil to 'know' the engine is running and it then sends power to the fuel pumps. And second B) the key is is in the start position. This activates a bypass circuit that bypasses the drive relay to ensure the fuel pumps operate while starting the engine/before the drive relay takes over. Turning the key to 'on' does not power up the fuel pumps. They may operate for a moment as the initial pulse of switching on the ignition briefly triggers the drive relay. But the drive relay does not keep the fuel pumps powered on when the pulsing signal does not continue as it would when the ignition is operating.

So, your engine may be getting fuel when you are starting it (the bypass circuit). But if the drive relay or the sense wire is faulty when the key is released to the 'run' position, the fuel pumps lose power and the engine will only run for a few seconds until residual fuel pressure drops.
 

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Discussion Starter #17
ghnl, When you say "sense wire" you're talking about the yellow wire from the coil?
 

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Discussion Starter #19
Tested the main fuel pump last night and it is not getting power when key is on or cranking. When I jump #87 to #30 on the pump relay I get 12v to the pump. I also tested in-tank pump by connecting to the battery and got a half liter of gas into a jug after only a few second of cranking. so, that works. I've read just about all threads on this issue and I think it's one of two things; a bad ground or main relay. Electricity is not my friend and I don't understand all this relay jumping stuff. I'm going to continue to find and check grounds but I don't know how to check relays. Pump relay is good. I'm thinking of replacing main relay (Beck-Arnley 203-0100, $29.) and that will eliminate one more potential problem from the endless list of things it could be. Any other thoughts would be appreciated.
 

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Look at the positive terminal on the battery. There is a wire that gets corroded and the car won’t start, the computer will come on but there isn’t enough current for the injectors to open.
I don’t know what years Alfa changes to motronic but the earlier electronic injection used a “fifth injector” and a thermal time switch which operates independently from the rail injectors.

The sputtering May be the Fifth briefly opening, but since it’s hot out, it’s not Really needed. It’s like a choke for fuel injected cars.

Give it a look, if it’s molded into the connector, cut it, clean it and put a new connector on it and see if she fires up.

Regards Richy
 
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