Technical Tipo 1.4 DGT fuel cut-off issue

[tmendonca31]

Hi all,

I own a fiat tipo 1.4 DGT from 1989 with a weber 32/34 TLDE carb. The car runs smoothly and with no fails when I press the throttle or when in idle. However, when the car is deaccelerating on low gears (2nd, 3rd) and the RPMs are below 2000, it tugs, like it had a lack of fuel. At that moment, if I give a little throttle or press the clutch, the problem is gone. According with haynes manual, I think that it might be an issue related with fuel cut-off valve or ECU, since the switching on/off occurs near the mentioned RPMS (1800). Have anyone else also experienced this before?

Thanks.

 

[s130]

Later Fiats with carbs had a "fuel overrun cutoff" solenoid on the carb. This was as I recall a simple needle valve that shut of fuel in the car idle and progression channels. Even with the throttle closed which is effectively the normal idle position the suck/venturi action would still draw fuel in via the idle and progression channel feeds.

If the valve is not cleanly shutting off the fuel then tugging may occur.

I would try disconnecting the cable to the carb cutoff valve and see if that cures the problem.