so i did a T2 engine swap into my 91, just replaced the engine, but the end product was that it idles a little high at 1500. i didnt swap out the rear end, so i still have the NA driveshaft, transmission, and entire rear end pretty much. when i let my foot of the gas in pretty much any gear it decelerates fine for a little bit, but then when i reach 23k down to 1700 rpms it starts to buck back and forth, im thinking its the drive shaft..? once you take it out of gear it rolls noramlly. im gonna try and redo the timing, since the jdm engine doesnt have the idle controller like usdm engines. my car is pretty much stock boosting around 10 pounds, and its my daily so i never beat on it. my tires are all balanced. idk..i was wondering if the NA driveshaft did this because its not as strong as the T2 one? and let me know if i should check anything else out.
ive searched the forums and i cant find the answer so any help would be appreciated!

 

Check your TPS, and see if it is within range. If not, adjust it and see if you still have this problem. I had issues like yours, and after buying a new (used) TPS, adjusting it using adjustment lights from Banzai, it now runs mint.

 

It's most lkely caused by a missadjusted TPS or a faulty Anti Afterburn Valve in the Air Control Valve (ACV).

 

thanks guys, ill check it tmr, im not quite sure how to adjust the tps to the right adjustments, but i guess ill just play around with it, and see if it works. is there a write up on it?

 

https://www.rx7club.com/showthread.p...hreadid=235007

nvm found one, and everyone else that needs to see it here it is

 

Green/Red wire should read 1 volt w/key to on and engine thoroughly warmed up as this is the easiest way to set the TPS.

 

Werd. This was the solution for me, in combination with setting of the idle adjust screw on the back of the throttle body. Thanks satch... saved me.