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Drove to about 20 miles outside town and it ran fine, coming back it started to stumble. First one big miss, then smaller misses. Power went way down and barely made it to the intersection home sputtering all the way. But trying to get up the hill it would not make it and pulled off and it died. Could not see anything obvious under the hood. Let it sit and although extremely hard to start, it did, seemed to idle fine, then put it in gear and no power. Figured screw it and tried to make it up the hill, it did, would not go in 4th and run at all, power was down in all gears. Made it home in second stumbling all the way, died at the gate at home. Let it sit and very hard to start again, but it did and I ran it to the shop to park it. It did not overheat, lights for the injection system have apparently been disconnected, oil pressure fine.

I’m figuring the obvious first, fuel issues and maybe clogged filters? After that, into the injection system and I’m dead meat there. Just for fun, I’ll do a compression check and try to start it in the morning. Oddlt, it did have it moments of “crispness,” so I’m still back to fuel as the culprit? Is there such a thing as a partial fuel pump failure? All other electric fuel pumps I’ve had experience with are either, on, or off.

Any thoughts? I've only had the car two months . . . ran fine until today.
 

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Was it particularly hot when this issue appeared? How much gas was in the tank? Did the low fuel pressure light on the dash ever come on?

The rear muffler runs right next to the gas tank. On particularly hot days the gas in the tank can heat up and cause symptoms similar to what you describe.

Joe
 

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Fuel issue?

About 90 degrees outside in slow traffic . . . tank about 1/3. Interesting, that's one I never heard of. I'll try to start it in the morning and see what happens. Appreciate the feedback.

Lon
 

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The most important question is what Joe asked . . .

Is the fuel low pressure warning light working normally and did it come on?

Until that question is answered, it's a waste of time to continue troubleshooting.
 

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1300 Gt Junior

my friends car a 1300gt junior has a similar problem. when the temerature is above 24deg. C and less than half tank the car shakes and then stalls. the other day it would not even make it up the hill. sometimes if you let it sit for 10 min everything clears up. we removed the gas cap to see if there was any differnce but nothing. NO WHAT?
 

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To check the low fuel pressure light, remove the air box and locate the low fuel pressure sending unit mounted on the top of the fuel filter. It is the only electrical wire to the fuel filter. Remove it and with the ignition turned on, ground the wire. I don't need to remind you that you are on top of the fuel filter and a spark would be a bad thing - right?

So if, when you ground it the low fuel pressure light glows, then you know the light works ( and the sending unit is probably bad).

Checking the pressure and the flow is a bit tricky. You can mount a fuel pressure gauge on the return side of the SPICA (TEE into it - DO NOT deadhead it). It should measure 10-20 PSI. Also check the flow. You should be getting .5 to .6 GPM.

The bottom line is if the pump is of unknown age you are probably smart to do a complete fuel system rebuild:

1) Replace the fuel pump
2) Replace the rear and the front filters
3) Replace the rubber fuel lines
4) Replace the steel fuel lines
5) Replace all the copper and aluminum seals in the front fuel filter banjo fittings
6) Replace the low fuel pressure sending unit (if Inop)

I say this from personal experience. A new pump is likely going to produce a higher pressure which will further stress an age weakened system. Today a fired up a new pump on my '69 and spent the next few hours chasing leaks. First just about every fitting on the front fuel filter fitting was leaking (I had it apart and reused the old seals - bad idea). Then a couple of the rubber lines cracked and needed to be replaced. Just when I thought I was done I noticed a pool of fuel midships. The steel fuel line was rusted and ruptured. No Mas!

Just do it all now and your done for the next twenty years.

Good luck!
 

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we found the problem!! the guy who rebuilt the motor installed all new fuel lines. the one from the filter to the pump had a tight bend or kink in it. as it got warmer the line was more flexabile and collapsed and the fuel was cut short or starving the carbs. A slight adjustment and she runs smooth. Now i want to replace that line as even thougt it is new could cause problems when it's hot out and because it is on the sucksion side of the pump. what type of fuel line do you guys recmmend that is strong yet flexable??
 

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Gprocket where is the low pressure light on the 1300 gt junior? the manual does not show any indication of where it would be. I found the low fuel light but no low pressure light?
 

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Gprocket is right, carburatorered Alfas doesn't have fuel pressure light. They have a simple engine driven fuel pump sucking from the tank and pumping to the carbs.
Erik
 
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