Update
After the Indy replaced the OVP, I no longer have the stalling problem when put in gear D or R.
So I still had 2 problems –
1. High Idle (1000RPM) when gear in P or N. 700RPM when in D or R.
2. Engine stalls immediately after start. It starts fine after a few attempts.
Here was my quest.
I replaced the Idle Control Unit (ICU) with another used one I had laying around and it did not make a difference. Actually, it was even worse. The idle kept fluctuating up and down and then eventually stalled… many times. So I put back the original ICU.
So I soaked and cleaned the ICV pretty good. I also noticed clicking sound like something was lose inside the ICV when I shake it a little. Anyway, after a good cleaning, I reinstalled it and the high idle was gone. After driving around for a few miles, I noticed the high idle came back up and this time it was worse than before. Idle was 1500 in P and 900 in D or R. I guess I killed it.
I replaced the original ICV with a used one, and this time the idle stayed at 650RPM in P and 550-600RPM in D. So I guess I’ve solved the high idle problem.
I still have one last problem – Engine stalls immediately after start. Sometime it goes like this when I start the car. Right after it starts and release of the key, the RMP would go up to about 1500 right after start then drops right down to 100-200 RPM like it would just drop dead, then shoot back up 800 RPM then becomes stable at around 650RPM. The entire process takes about 3 seconds when idle becomes stable.
I ordered and installed a new ICU and did not really notice anything. Except that when it stalls immediately after start, the second try ALWAYS start her right up. Previously I may have to try a few times.
Do you have any idea with my last problem?
Thanks