Can anyone explain this?

[Kwik_Cutty88]

So my car has been doing something weird, but now it seems to be becoming more frequent. At about half throttle when you are getting up to speed, only in 3rd gear and at 2500 rpm, it will suddenly act like it is going to downshift, and slow the car way down. If you get off the throttle real quick and get back on it, it will continue to accelerate normally. If you don't take your foot out of it, and give it more throttle, the rpm will just shoot up. Cables are adjusted correctly, and fluid is always full (doesn't really use any fluid.) Doesn't matter if the car is hot or cold. And it won't happen if you give it any more/less then half throttle. We have to pull the pan off to put a TCI lock-up kit in, so I guess then we can do some inspection. I'm thinking there might be something hung up in the valve body. Any ideas?

 

[Bonnewagon]

I had that problem on a 1980 Firebird w/T-350. It was the Governor, a bit of clutch facing material flaked off and was jamming up the Governor. It would try to upshift to 3rd, but then drop back to 2nd. If you floored it, it would rev a lot- hit third- then drop back to second. Luckily the Governor housing is easy to access and clean out.

 

[Kwik_Cutty88]

I had that problem on a 1980 Firebird w/T-350. It was the Governor, a bit of clutch facing material flaked off and was jamming up the Governor. It would try to upshift to 3rd, but then drop back to 2nd. If you floored it, it would rev a lot- hit third- then drop back to second. Luckily the Governor housing is easy to access and clean out.

I'll prolly check that too. I was reading up on shift kits and most of the consensus online was that some shift kits act funny and can do weird things at very specific throttle inputs.

 

[CWPottenger]

That is a common issue w/ 700R4's usually need to look at/change governor spring to move the shift point away from where it is. It could be an improperly setup shift valve for your engine/car/rear end gear combo also.

 

[84cutspreme]

I had this problem and it ended up being a torque converter that was to big of a stall speed

 

[Kwik_Cutty88]

I think the governor is still a 4500 RPM one, should really be a 5500 RPM. I finally got the car to act up while my dad was in it, and he said it feels like a 2-3 flare that some shift kits have. He said his T/A did it with a B&M shift kit, but when he rebuilt the transmission with a TCI kit, it solved the problem.