fast idle

Hi

first post replies appreciated

I have just re-commisioned my GTA from 13 year slumber, one of a number of small faults is the fast idle staying on even when fully warm, solutions please

Thanks
Phil

[mettersl]

Hi welcome
Especially as you are another person with a smart car interest too, I keep saying smart owners aren't all hairdressers here. There are quite a few smarts in the Raoc community. My daily car is a smart roadster coupe.
I see it's an atmo from your profile so it's some obvious things like air leaks, throttle flaps ( on both carbs etc).
Then seem less obvious like are all the linkages moving smoothly? It's a complex to set up.
If you have a look here there may be some help, the 310 and the atmo share a common carb set up and their are some links to check.
viewtopic.php?f=2&t=7513&p=78976&hilit=Carbs#p78976
I'm sure som more knowledgable people will let you know, but I'm interested in the result and I'm hoping to get my atmo running soon after coming off the road in 1997.
Cheers
Lee

......... fast idle staying on even when fully warm, solutions please

Hi there,

A lot depends on the level (revs) that the fast idle appears to be stuck at.
However if it around 1100 to 1200 revs, it most probably due to the operation of the "Accelerated idle" when the engine is warming up. If the oil temperature is between 15 and 35 degrees C, a timer relay stresses a solenoid valve which opens the twin choke butterfly by vacuum a fraction thus raising the idle revs to the revs stated above.
Now it will stay at this level until one of three things happen.
1. The oil temperature goes above 35 degrees C.
2. You drive at a speed that is sufficient to make the twin choke carb operate.
3. The timer relay releases which can be between 13 mins and 40 secs, and 16 mins and 24 secs.
If it is this problem then what I do is either accelerate hard to make the twin chokes operate, or if you have to drive slow because of traffic etc, go into neutral and "kick down" on the accelerator. It must be a good hard stab on the accelerator.
If it is not that, then the auto choke needs to be checked to see if the single carbs choke butterfly is in the vertical position when the engine is hot.

John