MartyCarloSS

i'm having an interesting issue with my speedo. i've got a 2000 t/a 6spd with 72k on the odo, and under heavy acceleration my speedometer just quits completely, then it'll come back on after a little while. under normal take off it works ok so i'm wondering if i have a sensor going out on me somewhere. my SES light popped on but i had it checked and it was for high idle condition because of a sensor on the A/C circuit and i dont think it's related. no speedometer related SES codes as of yet. any ideas?