Hesitates under load when hot

[Donstoy]

Here is a bit of additional info regarding the problems with my 1980 Spider 2000. When I have been driving for a while and it starts to lose power and chug, it still idles smoothly and if I take it out of gear so there is no load related to moving the car, it will rev normally in response to the accelerator. It is only when I try to drive that it seems to be starving for fuel. Then if I let it sit for a few minutes, it will drive again for a few kilometres before it repeats the power loss. Any thoughts?

[redcars]

This sounds like a fuel problem. Have you pulled the fuel sending until and checkedh the screen on the fuel inlet. I would also make sure your gas cap is vented. You could also blow out the fuel lines.

[TheBender]

I had a similar problem a while back and if memory serves me it had to do with the fuel return line from the carb to the tank. Created a vapor lock. Loss of power and also stalled out the engine and wouldn’t start again until after it cooled off.

[Mancda]

Hi. Just reading this thread as I am experiencing a similar issue to others in my 1980 FI Spider. It just started a month ago and then just died when I was driving and wouldn’t restart until it cooled down.
After some research and swapped out the ignition coil as it had died and this addressed it starting but it still jerks after driving for 15 min or so and usually around 2500 to 3000 rpm and mostly in 2 and 3rd gear.
I replaced the fuel filter but that didn’t help and when I cut open the old one is wasn’t dirty. Lastly I had drained the gas tank for an earlier project (rear bumper delete) and the tank was clean.
Curious if anyone found a solution to this problem that worked.
Thanks
Dan

1980 Spider 2000

[18Fiatsandcounting]

My guess at this point would be either a failing Ignition Control Module (ICM, mounted on the heat sink right behind the coil) or a faulty magnetic coil pickup inside the distributor. The two wires to the latter often go bad as well.

Other possibilities are bad plugs or plug wires.

-Bryan

[Simon124]

hmmmm..... that may be a positive indicator. Here is the system:



Note that the Carbed cars are VENTED GAS CAPS, the FI cars are SEALED GAS CAPS.

For information purposes: I think that the fuel tank and lines diagram for 1980 on Fi cars in the manual is misleading.

I followed it and connected my fuel take off to the port on the fuel level sender side of the two, but I now think that's the fuel return port.

[18Fiatsandcounting]

For information purposes: I think that the fuel tank and lines diagram for 1980 on Fi cars in the manual is misleading.

I followed it and connected my fuel take off to the port on the fuel level sender side of the two, but I now think that's the fuel return port.

That's interesting. I don't have a FI spider to check on this, but here's what I would do to verify which port is which. If you take a clean piece of hose, connect it onto each of the fuel tank ports in turn, and blow into the hose, the port that goes to the bottom of the tank (the fuel supply) should sound like you're blowing bubbles through the gas (which you are). The other port (the fuel return) presumably just dumps into the top of the tank, so blowing into that will just be blowing into the headspace above the gas.

Crude, but it might be effective to tell one from the other. Just be sure to blow into the fuel hose, not suck on it....

-Bryan

[Simon124]

I switched my lines and all is good.
Guess the image lost some detail accuracy during its digital switch.