[Joe Cs]

my 2-cents FWIW, start with the basics. first, REMOVE and thoroughly clean your throttle body. lets assume for now, your IAC valve is OK, but clean and pay close attention to the valve's pintle. next, double check your TPS and set to .54V. third, double check all vacuum lines especially anything connected to the upper intake or plenum. a vacuum line does not have to be disconnected to cause a leak. your 86 is 30+ years old, and those original vacuum lines could be showing signs of old age. check for cracks or any signs of deterioration. just for the hell of it, throw a vacuum gauge on it - you should have around, and relatively steady 18 inches. finally, perform a TV cable adjustment. the TV cable on the 700R4 (and 2004R transmissions) controls line pressure and shift points, as well as shift feel, and part and full throttle downshifts. if the TV cable is not adjusted correctly, it can cause numerous transmission issues. report back....

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