This car is in good shape. I have had it since 1995 and it has less than 48k miles (true mileage).

It had a new oxygen sensor last april, spark plugs and ignition sensor are less than 15k miles, and it was running great since last april.

Yesterday my wife came back from shopping and engine was running akwardly at idle. Engine stopped at street corner unless she touched the accelerator she said.

I found the coolant pump was noisy and pully had too much play. I replaced the pump this morning. Worn bearing.

I started the engine and find that it cannot run at idle. It dies if I dont touch accelerator pedal. It seems running a little rich but not sure. I can't know if it had fault codes because I disconnected the battery when I replaced the coolant pump.

I tested the auxiliary air valve and cleaned it although it did not look dirty. The resistance is 8.2 ohm which seems good to me.

There should be a way to test the throttle switch but I don't know how.

Would it be the way to go or do you suggest I look at something else?