Isuzu Repair: Mystery Carb Sensor, partslocator, wire connections

Question
I have an 91 Isuzu P/U w/ a standard tranny.  I just got the carb re-built (part # dfp384-206) and was told that I have a bad sensor on the top of the carb.  I am also told that I have to buy the entire upper half of the carb just to get the sensor!  This is the very top sensorr on the carb.  The truck will die on me and idle roughly until I tap on the said sensor.  After tapping, it will run fine.  This sensor has a harness attached to it and runs to another sensor on the carb.  Can I get this sensor by itself?  Everything else on the truck is working great besides this.  If the sensor can be bought seperate, do you know how or where I can get a part # for it?

Answer
I hate to say it, but probably not. Not new anyway. try to go on a website that searches for parts for you, like carparts.com or partslocator... That is the only way I know of to get it. try taking the sensor off and cleaning it and check all the negative and ground wire connections. 90% of the time it is a problem with the ground that shorts out things. Even check your main ground for your truck.
But besides that I don't know what you can do. Try to find a carb specialist on the web and get part #s from them and see what happens.
Sorry I could not help any better than that.
Derek