89 choke stays on.
 

My 89 montero 4 cyl has a high idle when cold. The choke stays on for 15-20 minutes. I assume it's choke, it stays at 2500 rpm. Temp gauge never reads past 1/4. Once really warm it will drop to a steady idle at 8-9 hundred. This can't be normal? I figured it was a thermostat stuck open, but that isn't it, new one just installed and same problem. It's as if the car thinks it isn't warm but heat blows hot, and engine is def at operating temp. Thoughts?

coolant temp sensor?
 

Not very familiar with that model year but have you checked your coolant temp sensor to see if its working? Total stab in the dark there.

4 cyl what.
diesel? petrol? unicorn?

sensors. all of them.

A choke on a diesel engine? I doubt it. On a unicorn that's another story - choke on a unicorn and you get a no go condition :)

...well it might not be a choke issue at all.
the only thing OP actually knows is that idles high then drops.

"choking the unicorn"... sounds like somthing you might pay $200 an hour at the brothel for...

Thanks, I did the coolant temp sensor before anything else, and no dice. The is a second sensor on the thermo housing with a single wire. I'll try that next. Anyone know what that one is called? Thanks for help. Its a hybrid solar/ unicorn powered motor. Cutting edge tech for 89

Try a whip on that unicorn :)

try a different mix. i find mine fouls plugs at 25 unicorns:1 sun, but running it at 40:1 there's no problems.