Random idle drop

[blackcoupe]

Have an s14 sr motor in a s13.

Issue started randomly today and I just wanted some input on where to start here. It's been driving fine for the last few months until now.

When the clutch is disengaged or I put it into neutral, idles drop from 950 to like 700-600 and it sits there stumbling for a while until the ECU corrects it back (takes like a minute though) there is a hesitation when engaging into 1st gear also. Another symptom I realized was that every time I let off or disengage exhaust backfires a little more than normal.

Stock motor, stock exhaust, stock recirc bov.

Possible vaccum leak? or dirty IACV?

[Dilbeckskate]

Mine did the same thing when mu injectors were dirty, like I clould be going down the road and floor it and the RPMs would drop like crazy for a split second, then kick back up, and at Idle it would bounce around, I took and put some injector cleaner in my gass ( rubbing alcohol will work 2 ) and put some Marvel Mystery oil in my oil and it made it run fine, hope I was some help, lol