[MSCW list] Losing Power 1989

[Gail Furman]

I'm the original owner of a beautiful 1989.  I lose power when accelerating; the engine sounds like it's revving when I step on the gas, but the car doesn't really move forward.  At first, it was only on the highway when shifting into higher gears, but lately, I've noticed that it's happening occasionally in lower gears (2nd and 3rd), particularly if I have a passenger.  I do little highway driving, so it's been going on for quite some time.  I recall this happening 10 or more years ago; the mechanic was stumped until the old Miata magazine had a brief piece about it being some kind of valve or something, and he was able to quickly fix it (I knew I shouldn't have thrown all those service records out!).  I looked through all my back issues, but couldn't find the information.

Any advice would be much appreciated!