rx7erik

please help my identify this part because my car is missing it and i believe it is the cause of my rough idle. thank youuu

RotaryRocket88

iTrader: (7)

You circled both the boost/MAP sensor and the variable resistor. The MAP sensor is an unlikely cause of rough idle, but the variable resistor adjusts idle mixture. If you jump the initial set coupler (2-wire plug by the leading coil), you can turn the resistor towards (L)ean or (R)ich. It should be somewhere towards the middle, but you basically adjust it and see if the engine smooths out.

Other sources of rough idle may be vacuum leaks or TPS problems.

rx7erik

well the thing its specifically missing is that little rectangle box in the center of the circle. whats that?

myfc3s

iTrader: (2)

That there maps out how much fuel and ignition should be on idle or WOT. Is that picture your car. i am a little confused if its missing? If not yes you do need that.

rx7erik

thats a picture i found on the internet. whats the name of the part myfc3s just described?

satch

iTrader: (1)

The little box which would have an electrical plug and a vacuum hose connected to it would be the "Boost sensor."

rx7erik

would the boost sensor cause a rough idle though? what in that circle would cause a rough idle

myfc3s

iTrader: (2)

Its been so long since i have used the stock ecu, but from what i remember the idle stayed the same when you detached it until you rev the motor. Have you disconnected the air intake duct? The rubber tube the clamps onto the turbo and the AFM. Another problem that may have done that is putting a bypass valve or a blow off valve.

rx7erik

actually its the thing next to the rectangle box. to the left of it. thats missing. can you tell me what that is please?

satch

iTrader: (1)

That would be the Variable Resistor which helps govern the fuel mixture at idle. W/o the resistor the ECU will rely on a default setting. The resistor also helps to set idle speed to a small degree.