1987 porsche 944 auto only works in reverse

as both these gearboxes are made by vw they are interchangeable.

sounds like the gear rings ? worn need to replace or get a used trans? from a u-pullit yard?

check sensor on rear of trans?

The transmission is worn. The cheapest fix is changing to a high quality synthetic fluid. This will allow for easier shifting when it is cold.

every 9,000 miles or 9 months which ever comes first with synthetic oil and Bosch Filter.

if we can afford the car then go by the relay? pelican parts or e-bay ?

check the abs pump fuse .the abs pump or a sensor could trigger it. get a scan done...the code will tyell you what is wrong

I'm assuming that this is a 5 speed stick car because you mentioned 80-90 oil. This car has a transaxle, not a a separate transmission and differential. The transaxle houses the transmission gears and the differential all in one housing. There is a drain plug on the bottom a fill plug on the side. Here's a link to one of the best do-it-yourself 944 sites on the web. Click on the "garage shop manual" link in the sidebar and scroll down to "transaxle fluid change".

http://www.clarks-garage.com/

check transmission fluid .if low add to the right amount. if looks dark brown smells burnt.change fluid and filter.

change your transmission filter: no or, very little movement and, no shifting indicates a clogged hydrolic circuit
do not continue to drive your car at that rpm until you fix this as engine damage can occur