idle speed adjustment on 20V ST - Toyota Nation Forum : Toyota Car and Truck Forums

badtoy · 12-24-2004, 05:57 AM

Hello,

just had a successful transplant about a month ago with a 20V silvertop on my AE92 sedan. Everything is working fine now except for a small minor problem. My idle rev is too high, its about 1.7K RPM

I had all possible causes checked like

- ECU: i thought my ECU was faulty but when I plugged in another ECU I still have that high RPM on idle speed. Tested also my ECU on another 20V engine and works fine.

- vacuum hoses: checked everything, I might have left a hose open but all is well.

- thermostat/ temp sensor: working fine also

do you think its just an adjustment on the Idle speed controller? where can I adjust this?

Kwanza · 12-24-2004, 12:58 PM

Check the TPS, AFM, and timing.

micro214_kp61 · 12-24-2004, 10:16 PM

hey Mike.. welcome to TN!

check the AFM, someone told me that if it was angled a bit off, it won't idle properly. also check the TPS like Kwanza said.

badtoy · 12-25-2004, 06:58 AM

ey mike... thanks,

i'll just have my car brought to the shop to have the throttle body clean and do some adjustments on the TPS and timing

***REN69*** · 12-25-2004, 08:53 AM

Not sure if the 20V would have one, as I've never dealt with a 20V in person. But have you tried the idle screw?? I know the Bigport 16V's have it right where the intake port would be, its covered by a black rubber cover. With my car I've noticed that if I raise the idle leave it for a bit, then lower it to where I want it, it will idle always at that setting.

surfa · 01-16-2005, 10:35 PM

Hi,

I have a similar problem. I got a 1988 corolla with a 4A-FE engine in it.

I had the starter motor replaced by a mobile mechnic about a week ago. I saw some sparks came out near the starter moter during the replacement. Possibly the positive wire of the starter had short circuit with the body.

Initally it was ok. But after a few days, the idle speed suddenly gone to 2100rpm even after the engine warm-up.

Any one may know if shorting the positive wire of the starter motor to the car body may cause any damage to ECU?

Will the engine faulty light comes on if the ECU is damaged.

Any helps are very appreciated.

MississaugaGTS · 01-18-2005, 10:58 AM

Surfa....

I don't think the shorting would affect the ECU as the engine is grounded directly to the battery and body, therefore there is no route for current to flow through the ECU. The only way this may have damaged the ECU is if the short was on a sensor ground wire or something of that nature.

MississaugaGTS