1989 gmc k15 4x4 automatic 3 problems

[lopezf43]

i have 3 concerns the first one my speedo only works when it wants ive already changed speed sensor took cluster out and cleaned all connectors . yet i got no change. number 2 fuel gage only works from 3/4 full to full another words at 3/4
im emty between 3/4 and full is half tank and full is full .I already changed sending unit and cleaned contacts on gage . no change. and last adle gos up to 1500 rpm i replaced IAC and TPS and MAP Sensor and EGR and some times it blows black smoke burn rich. can any body help. thanks

[2000CAYukon]

Is the high idle all the time? If so, check the TBI gasket for a leak. Spray TB cleaner around the base, especially at the rear of the TBI unit. If the idle changes, the TBI gasket should be replaced.

//2000CAYukon

[lopezf43]

cool thank you so much i will check it