FZJ73L Fast Idle when hot

[LC Colombia]

I am a new user and new to owning a Land Cruiser. I purchased a 1997 FZJ73L with 1FZ-F engine here in Colombia last month. It is a great vehicle and pulls strong up our 6000 plus foot mountains even in 4th gear easy.

My problem:
I replaced the carburetor last week with a brand new Toyota replacement (the original carburetor was completely buggered by the last owner). When the engine is hot at normal running temperature it idles very high, around 1800 RPM. I know this is not normal.

Any suggestions?

Couple observations: engine runs strong and very smooth once it is warmed up for about 15 minutes. No knocking or other noises from the engine even under load going up our 6000 plus foot mountains. Engine does not burn oil at all and does not smoke!

I want to resolve this problem quickly as a fast idle like this can cause overheating, not good.

 

[ozcruiser]

I would be checking the sensors on the engine but maybe the heat sensor is playing up not cutting the idle back after cold start.

 

[LC Colombia]

ozcruiser, thanks for the suggestion, I will check the sensors tomorrow. Took a nice long off road excursion today and she ran great except the high idle after about an hour of rough terrain.

Another observation, when I cold start she starts up easy and idles at around 1300 for about 5 minutes then drops down to a normal 700 rpm. It is only after a long ride that the idle increases to 1700-1800 and will not come back down.

 

[ozcruiser]

Maybe focus on the throttle position sensor as it sounds like your carby is gummed up with crap

 

[LC Colombia]

ozcruiser, thanks again for the suggestion. The carb is brand new just installed three weeks ago. I found a bad vacuum line today, I replaced it and I think this has resolved the problem.