Could anyone possibly explain this for me? I know what it is, and how/why it works.

My issue is, it only happens if the temp outside is about 50 - 70 degrees. Any colder, and it runs up to 2,400 or so, then just holds around 1,700RPM. I do always start in neutral, so I'm not disabling it.

Should I be concerned that it's not doing it? It's a fairly new engine (installed in 98, with about 10,000 on it now), so I would think that it's ok in itself...

Thanks

 

I would not be worried about it not working-its function was to warm up the cat quicker at the expense of engine wear.

You only need fast idle to keep the engine from stalling, lower the speed when cold the less wear.

 

right, I figured as much. I'm not too worried about it, but the fact that it doesn't do something it's supposed to makes me wonder if something, somewhere, isn't right...

 

I guess I'm one of the semi illiterate. I read this post three times and I'm not sure what is being asked.

Normally you get an approx 3000rpm upon start up for 17 secconds (count 'em).

IF the Air Bypass Solenoid is malfunctioning or the relay that controls it is acting up.....then you might just get an approx 2400 or so rpms for 17 seconds.

After 17seconds the idle drops down to approx 1200 to 1500.....that all depends how well set the fast idle cam/thermowax has been set up. And after the water temp rises up the idle should go to 750 for an idle.

If it never happens (17 second fast idle), then the you are starting the car in gear.....or the water temp switch is disconnected/malfunctioning......or the neutral switch is in the *in gear all the time mode*.

The 17 second event should not ever be happening if you are starting the car in gear. If it is...then there is a neutral switch problem. Located on the right side of the transmission. Two wire circuit.