Delta Delorean wrote:Admin-bloke wrote:Check for a stuck valve in the idle speed control valve.
I have cleaned the inside with brake cleaner and compressed air about a month ago.
But i have never checked if the thing actualy works! Car is in pieces now, i will check it once everthing is back together.
Is there a way to trigger the valve to see if it moves? Just run the car and let it warm up?
Use a test car battery and fused wires.
Disconnect the idle valve if not done already.
Apply 12v to the centre pin of the idle control valve.
Apply the 0v briefly (less than 1 second) to one of the outer pins, the valve should fully move in one direction ie move fully opened or fully closed.
Apply the 0v briefly (less than 1 second) to the other outer pin, the valve should fully move in the opposite direction ie move fully opened or fully closed.
The valve should move freely, as in if you had the control valve in your hand, you could flick the valve open and closed if you quickly flicked the case around.
A quick check if the ecu is controlling the valve is to connect it to the wiring but still have it off the car. With the valve in the closed position, turn the ignition key to position 2, the ecu will slowly move the valve open in a controlled manner.
One thing to note is that the air flow is directional, the air should flow in one direction, there should be a small arrow on the casing. This should point to the direction of the brass pipe that is a push fitment under the inlet manifold.
I think you're better off isolating the systems that can cause the engine to hunt, one of which is a contaminated oxygen sensor giving poor/ slow switching feedback. You can electrically disconnect this at the back of the drivers seat under the wooden board, behind the grey rubber bung in the fire wall. Disconnect this and tape over the bare electrical spade connection at the blue wire that goes to the lambda (fuel) computer.