Transmission Problems

[jgarced]

I have recently purchased my first Nissan, a 91 240sx hatch. It has an automatic tranny which is bugging out.

When I take off it doesn't shift until it hits 6k rpm. I run it on the highway at about 60mph and it stays running between 4-5K rpm. I am not sure how many times it shifts since I've only driven it once for about 60 miles to get it home.

It has a bad exaust leak. I ran the codes and it only showed a knock sensor code.

Does it sound like the tranny or the computer?

Please Help.

[orion::S14]

Engine cmputer does not control the tranny.

The auto has a seperate controller.

Sounds like a bad tranny.

Look for a new one here: www.car-part.com

- Brian

[jgarced]

Well that's the computer I was reffering to. Does that sound like it's possible?

I'd hate to have to drop a tranny in it. I was hoping to get started on a turbo setup first.

Either way the guy I bought it from is gonna have to fork over the cash to replace it. I just bought the car and noticed it on my way home.

[nightwalker]

Hate to break it to you this way, but you may have a hard time getting the guy to fork over the cash for the tranny.

Sounds like a tranny on it's way out. Check the tranny fluid to see if it's ever been changed. Most people who own automatic cars don't do the recommended tranny fluid and filter change.

[kandyflip445]

Make sure the O/D switch is on.

[IGSDann]

Do a 5 speed swap - Fixed :2f2f:

It's really not that hard of a swap...

[jgarced]

nightwalker, I'm sure I can "convince" him to put up.

Yeah I was afraid it was the tranny. I wanted to do the 5 speed swap anyways, just not so soon.

I'll do a search for what's needed to do the swap.

[kandyflip445]

Check your fluid condition. Pull the tranny dipstick and take a little bit and rub it between your fingers. Does it feel grity? Check the throttle sensor. Turn the key to the ON position with the engine OFF and with the throttle fully closed it should be .5v with the throttle open it should be 4v.

Those are my first guesses. It would help if you knew how many shifts it did. Also if it shifts into any other of the other gears at the wrong RPM. Also check that your shifter goes into every gear selected. Slowly move from Park->R, did the car do anything? Then from R->N, same thing, and so on. Make sure there is every gear change. It might be the linkage isn't adjusted right and you're not in D. Make sure the OD switch is working properly too.

[97240via]

Check TPS? And check the computer (TCU: Transmission control unit, located on passenger side, near ECU). Then check the transmmission. This is my guess and that's what i have done to my car. Turned out that the TCU is bad.