I have a aristo swap single turbo, I changed front mail seal and have a low idle when car warms up . Between 300-500 , prior to that i was idling at 800-900. Checked for vac leaks . What else can i check to see why its low now, at lights my oil pressure light will come on. Checked oil not low. It will cut off when i slow down real quick. If i coast to a stop sometimes it will be steady at 700 then when i put break on is starts to drop. What can it be?

 

It might be normal.. the car might have settled?

Bump though.

My 1UZ does the same, it drops 200-600 when its warm.

 

300-500 is low.. 800 should be normal.

I have the opposite problem, my car is idling high... hmmm

 

My 1uz

1000-1200 when cold, depends on how cold the temp is.
700 - 750 normal
550 - 600 low, when the car is @ operating temp.

Its the ecu saying - there is no air-con, the engine temp is optimal, charging system load is low, what i will do is go into sleep mode, but still allow the engie to tick over as low it needs to be.

If it sh*its you, what you can do is screw the idle screw in a little till it reaches your desired revs.

 

It could be a blockage in the Idle Air Control valve. Someone cleaned theirs a little while ago and it was all sorts of gunked up. If that doesn't work, there is always the idle stop screw adjustment method.