Club126UK

Fiat 126 Chat => Fiat 126 Mechanical Problem Solving => Topic started by: Minijohn on November 25, 2018, 11:59:57 AM

Title: Wires to carburettor query
Post by: Minijohn on November 25, 2018, 11:59:57 AM
I have a 1990 air cooled car.
On the carburettor there are 2 wires attached coming from the wiring loom.
I only have a Haynes manual for cars up to 1987 and this wiring isn’t shown.

I read the 126 BIS has a device to increase the engine speed at tick over when under load - does my car have the same device? Maybe that’s what these wires are for?
or
Fuel cut-off solenoid ?
Thanks in advance
Title: Re: Wires to carburettor query
Post by: korky on November 25, 2018, 12:39:47 PM
Hi sorry cant help you ,but you could help me ,do you know what it is and what it dose the box on the left of the engine bay ..... been said that its something to do with a type of caterlist ..... cheers
Title: Re: Wires to carburettor query
Post by: Minijohn on November 25, 2018, 02:25:18 PM
It’s a charcoal canister and this is what it does......

Charcoal Canister. Part of the car's emissions controls, this charcoal-filled canister's job is to absorb fuel vapor that would otherwise vent out to the atmosphere, causing pollution. Vapors trapped by the charcoal are released back into the engine through the purge valve and then burned.
Title: Re: Wires to carburettor query
Post by: 1973/126 on November 26, 2018, 08:11:09 AM
 One of the wires is for the cut off valve. Can't remember what the other one does.
Title: Re: Wires to carburettor query
Post by: Rusty's Uncle on November 26, 2018, 01:32:30 PM
I have a 1990 air cooled car.
On the carburettor there are 2 wires attached coming from the wiring loom.
I only have a Haynes manual for cars up to 1987 and this wiring isn’t shown.

I read the 126 BIS has a device to increase the engine speed at tick over when under load - does my car have the same device? Maybe that’s what these wires are for?
or
Fuel cut-off solenoid ?
Thanks in advance

I have two brand new late Weber carbs here that both have the cut off solenoid. One is dated '92 and has a single spade connector , the other is '96 and has two spade connectors, one on the solenoid and one on the throttle stop post. I just took a picture but then realised that I have long since given up trying to post pics here. If anyone is wanting a new late carb do let me know as I am open to offers  :)
Title: Re: Wires to carburettor query
Post by: Minijohn on November 26, 2018, 02:13:00 PM
Thanks for the helpful replies everyone.
I’ve done a bit of testing with my multimeter.

The cut off solenoid has 12v supply with the ignition on, 0v ignition off - as you would expect.

The other wire does go to the throttle stop and shows a different reading whether the throttle is opened or resting on its stop.
I’ve seen this before and realised it’s an economy device - when the throttle is closed and the engine is going faster than tickover (on the overrun - therefore no fuel is needed)) this device will operate the solenoid to stop the fuel supply, thus saving fuel.