I just bought an automatic 1990 Prelude for the gf. I bought it with this problem, and I can't seem to figure it out. When you start driving everything is good, then after about 5 minutes, out of no where it feels like it goes into neutral, and the rev's go up, but you don't move at all. It gets more [freak]ed up from here. If you turn off the car, and let it sit for a minute, once you start it you can start driving again, but it won't last as long.
The longer the car sits, the longer you can drive without this happening, to a max of about 5 min. If this happens, and you turn the car off and start it up really fast you can drive for about 10 seconds...

I've checked the ATF, and it's full. Looks a little dark, but not too bad. The S3 light on the dash is flashing too. The engine light is on, but I checked the CEL, and it's for air intake temp sensor.... I don't have a clue whats wrong..... Maybe the Auto trans module? maybe a selenoid? Any Ideas??

Thanks


BTW I have been searching for 2 days before I decided to post.

 

If I were you, I would drain the fluid out and refill with genuine Honda ATF. It's the cheapest and easiest to start with.

 

Didn't work. Any other suggestions?

 

Don't check the atf level. Replace it. If you have the problem after doing so, the car needs a new trans. From what you describe it sounds like it's slipping.