rough idle

[Bacon_Fish]

about a week ago my s13 was running really bad.
it was idling rough,went through plugs and wires.
change the dizzy cap and rotor.
still there.
found out it was the egr valve.
i changed it and the BTP.
i also changed vacuum lines.
had a check engine light this all started.
engine coolant temp sensor.
got that taken care of.
now,my car still idles rough but runs much better.
what else could be causing an unusual idle?
thanks in advance.

[dorkidori_s13]

a bad TPS, TPS is getting wrong voltage, throttle plate is gummed up and sticking, IACV is gummed up, sticking or improperly adjusted, improper plug gap, dirty MAFS, bad knock sensor, improper torque around intake manifold nuts, bad/rotten intake manifold gasket, timing is off, a vacuum leak you missed somewhere on the motor (especially BEHIND the engine on the vacuum routing plate)

[Bacon_Fish]

throttle plate i cleaned a few days ago(i left that out)
the plugs i pulled first awhile ago,they were gaped at .48,got knows who did that,i gaped them to .40,fsm says .39-43,so.
thanks for the info! much appreciated.��

[NismoDriverS13]

I'm having same issue...looking through pretty much everything. also had a misfire in the #2 cylinder. just take it one thing at a time, good luck.

[Bacon_Fish]

a vacuum leak will cause a misfire.
i found my idle problem; manifold leak.
gasket took a poop,nothing like some good ol' carb cleaner couldn't find.

[BoostSlideWayz]

You may need to just replace the IACV. I don't know what kind of engine you have, but sometimes KA's have them go bad out of no where. But you can adjust your idle simply from turning the screw. But you need to be careful with your adjustments.

another thing could be the maf... while your car is running... unplug the maf... if the idle doesn't change then your maf is bad.