Hi I am new to this forum due to the fact that I just bought a Grand prix gtp. It is a 98 with 61k miles. The transmission feels like it slips a little bit when accelerating from a stop. Also doesn't go into reverse. I looked under the hood and saw at the top of the tranny a circular harness plug had fallen off. The owner believes the tranny is no good. I am hoping that it is just the plug and that when I pick it up on thursday I can just plug it in and have a 500 dollar gtp with a very simple fix. Is this plug some kind of electronically controlled shift mechanism? Could the issues it'* having really be something that simple, or is it to good to be true? Thank you for your input and opinions in advance.

If that was the harness plug that goes in sideways on top of the tranny, and it wasn't plugged in, the vehicle wouldn't shift at all....does it shift?

If the transmission harness was not connected , both shift solenoids would not be getting power, which means third gear.....so if you stepped on the gas there would be no torque starting off in 3rd gear and it wouldn't shift out of third gear......

yes it'* that one! And idk if it cycles through 1st 2nd 3rd ect because I didn't really drive it but a couple blocks. If you mean shifting as in going from park to neutral to drive, it does do that. You can put it in drive and it will go. Just no reverse.

also will add thay I babied it really gently so it never really got a chance to cycle gears like it would normally. I did notice if I stepped on it 2 hard it would shudder almost like a bad cv axle feels

I concur, if the trans electrical connector is NOT plugged in, the trans will default to 3rd gear ONLY when placed in DRIVE. This is called 'limp home' mode. I wouldn't go romping on the throttle when its like that. Its like starting a manual car in 3rd gear and dumping the clutch at 3000RPM.

so by the looks of things so far, i should be able to just plug the connector back in and be good to go? Haha. I don't belive the tranny should be shot at only 61k miles

You'd be surprised what can be done to a tranny in 60k if its been abused. I'm curious as to WHY it was unplugged??

I'm HOPING it just rattled loose haha. I mean the car belongs to a senior citizen, he towed it behind his motor home and used it as a get around car for places he visited. Highly doubt it was abused. The engine is clean as a whistle and the car purrs like a kitten. Seriously looks cared for well

"Towed it around"? Look at your tranny cooler lines and see if you see any type of tap in for an external pump system or whatever. These cars cannot be towed with the front wheels on the ground and I'm wondering if he did that without having a oil pump connected to the trans to keep oil moving inside of it. If he towed it without it, more than likely he fooked the trans.

worst case scenario, what does a replacement tranny on one of these cars run? I'm sure i could manage the labor. I've built a few sr20 powered nissans in my day, and I do know that whenever I grenaded a tranny on my boosted sentra or 200sx, I always able to find another tranny for under 300 dollars and switching them out only took me a few hours. the domestic scene however, I am new to