Lukewarm engine won't start

When my 97 Tacoma is lukewarm, like after being parked for 20 minutes after driving, it won't start. When it's dead cold or operating temp it starts fine?! When this happens, it will start with a shot of carb cleaner down the air cleaner?!
Also, there is an error code for "lean condition". I've replaced the temp sending unit, the O2 sensor and cleaned the MAF sensor.
Anybody else encounter this problem? Are they related?

Thanks, and if I don't check right back, I have very limited internet access.(About once a month)(Dont' ask)