When I start my 88 4runner it idle normal but when I give it gas n let off it i dles at 1900 rpm

 

Throttle linkage or throttle body hanging up

 

The throttle cable is 'fraid could that be an issue

 

Yes if you meant frayed.

 

The cable could be catching in its sheath. Or the throttle return spring is worn out. You can buy a spring kit at AutoZone for $5 and find one that's close enough to cut down. Took me a couple tries to get one strong enough, had to keep cutting off a coil at a time.