1996 Dodge Intrepid Transmission

It seems like you're trying to say it's not shifting properly and the engine is running too fast. That is what happens when the Transmission Computer detects a problem and puts the system in "limp" mode. That is when it stays in seconds gear to allow you to drive slowly to a repair shop. Your mechanic will start by reading the diagnostic fault code(s). Those will indicate the circuit or system that needs further diagnosis.

The most serious codes are something to the effect of "Gear ratio error". That means based on the engine speed and the gear the transmission is in, the wheels are not rotating as fast as they should be. That typically means slippage in one of the clutch packs and the need to rebuild the transmission. If your mechanic has a Chrysler DRB3 scanner, it will display the "clutch volume index, (CVI)". That is a set of four numbers indicating the volume of fluid it takes to apply each clutch pack. An experienced transmission specialist can tell how much life is left in each one by those numbers.

The least serious codes refer to the input speed sensor, (engine speed), and the output speed sensor, (wheel speed). Those are used to calculate road speed for the speedometer, so if the problem is related to them, usually the speedometer stops working too.

It's important to understand that diagnostic fault codes never say to replace parts or that they're defective. They only indicate the circuit or system that needs further diagnosis. You may be able to get an idea if there's an electrical problem or a mechanical one by when it goes into limp mode. If you start the engine, shift to "drive", and it starts out in second gear and stays there, it's usually an electrical problem, because clutch pack slippage hasn't had a chance to occur yet. If the transmission starts out in first gear like normal, then goes into limp mode after one or more up-shifts have occurred, it's most likely due to slippage. You have to turn the ignition switch off and restart the engine to get it out of limp mode. Sometimes you can nurse it along for a few weeks by accelerating harder than normal to delay the up-shift, then let off the accelerator momentarily to let it shift with no load on it. With no load, there's less chance of a clutch pack slipping during the shift. Once it's solidly in gear, accelerate the same way up to the next up-shift.

Slippage can also occur during down-shifts when you're slowing down. I don't have a trick to avoid it going into limp mode for that.

You need to start by having the fault codes read. There's nothing so far that points to any sensor.

The transmission control I think you're referring to is the Transmission Control Computer. Chrysler's name for that is the Electronic Automatic Transmission Controller, (EATX).