1979 Fiat Spider Stuck Accelerating or Idles Extremly High

[Willards9]

Greetings Everyone,
I apologize if this has been tackled before in another thread with a better title but it's a thread I have been unable to find. I have a 1979 Fiat Spider that is, for a lack of a better term, stuck accelerating. So the last few times I drove the car I encountered a problem with the car continuing to hold power almost like engaging cruise control on a modern vehicle. The only way to remedy this was to take the car out of gear, press and release the gas pedal a few times. The three or four times it did this it was corrected almost immediately by exercising the above remedy. However, this past winter I was staring and warming up my Fiat for its monthly run to keep everything operational, and it happened but messing with the pedal would not correct it. Now I'm stuck with a car that starts right up but idles at 3500+ RPMs. I have tinkered with the carb on my own for the last few weeks trying to correct the issue to no avail. I've also searched a plethora of forums but haven't found anything similar or helpful. I would appreciate some assistance with this matter. Something has to be stuck causing the car to rev the engine up to 3500+ RPMs. I appreciate the assistance with this matter and thank everyone in advance for the input.

Best,

BW Schimke

[kenncarp]

Check all of your throttle linkage. My 79 did that a couple times, and it ended up being the lever that connects to the rod, which connects to the carb, i dont know the name for it, kept getting stuck. I would also check to make sure your flaps in your barrels are somehow stuck open. Good luck!

[bobplyler]

The best way to fix that is to replace the carb. A plus is that you will notice much better performance. You can use the stock manifold, but a single plane will provide even better performance (but it's not necessary).

[spidernut]

1. The most likely culprit is a sticking fast idle mechanism. It is operated by the choke. The internal parts can get sticky and cause this issue. Remove the choke, inspect, clean and lubricate and you should have the problem solved.

See items 58-64...this is what gets gunked up and sticks



2. Check your linkage and the spring in this photo:



3. Check your floor mat to ensure it isn't getting caught on the pedal