i have a 1994 olds cutlass supreme and it won't shift down when i stop. i have to manualy shift it down as it stays in high. i put in low and start down the road it shifts up to 2nd then as i get faster i shift to drive. but when i slow down or stop i have to shift down or it won't go. when i was changing the starter i found transmission fluid in my modulator valve and line going to my motor, i went and got another modulator valve and now it won't shift down. what i find really strange is i got the valve for $20 at one store and some part stores wanted $75 to $100 for one. do you think i got the wrong modulator valve? or will that even cause my trouble? thank you for any help.