cylinder head temp sensor, what the brain thinks Options

[worn]

Well, I have been tweaking the MPS. I still am having low torque below 2,000 rpm, making smooth transitions to speed a bit more dramatic than I would like. I think that the cam may be playing a role here that I may never tune out completely. Now over 2,000 is another story (IMG:style_emoticons/default/laugh.gif) (IMG:style_emoticons/default/w00t.gif)

The point of this post is that if you are fooling around and the cylinder head temperature lead (I think it is Temp I) comes undone, the brain sees infinite resistance. It therefore, on a warm summer evening, thinks the motor is frozen cold and dumps in fuel. It won't start. You have spark, you have fuel, but the thing is flooded to the gills. Nooo, its EFI! Yep, flooded. (IMG:style_emoticons/default/hissyfit.gif)

So I started thinking that a spare might be in order since no start can mean travel by foot - or used to before cell phones. An alternative would be alligator clips to simply ground the lead. That way the brain would think the engine was hot and you could limp home. My list of spares on a trip away from home is growing.

[stugray]

Worn,

My recent experience says you are correct. Short the lead to ground.

I had thought that I could use the stock CHT to tell how my car was running with carbs.
However with the stock CHT sensor I chose, the resistance goes to zero at about 280 deg. F.

Not too useful except to tell you the engine is warm enough, does nothing to help determine if it is too hot.

That might not be true with all CHTs as Brant points out, there are at least three different sensors.
The ones I got are known as 2252 type. That means they read 2252 Ohms at 25deg. C and approach a short at about 150 C.

Stu