I have a 92 Doge Stealth. The tranny will barely go in drive, but does fine in reverse. Is the tranny shot or maybe a sensor?

 

You may be in 3rd gear and reverse only. If so you would be in limp mode. The most common problem I see with a bunch of people is the capicators leaked on the TCU(Transmission Computer) and screwed it up. Its under the middle of the dash, take off the walls on each side of the driver and passenger seats, and open the TCU and you will be able to see or smell if its fried.

 

If you put in a cool air intake you shifter may be getting jamed against it or there may be another obsturction in the way too. Its located right below the air intake. Its a metal shaft sticking up. You may need to get another peson to change the gears to see if the rod it moving freely.