Deceptik1

iTrader: (6)

What's the idle supposed to be set at on a 93 SC300. Mine sits at around 6-700 rpm and I want to raise it to alteast 900. I was trying to find where the idle set screw is and couldn't find it. Anyone know where its at.

SC300T

I don't think there is one.
There is an IAC Idle Air Control Valve that does the same purpose... It meters air past the throttle plate when the throttle is closed at idle. As far as I know, it is not adjustable. Could your throttle position sensors be off a little? Ignition timing and plug condition can also affect idle speed... On a 1992, you can advance the timing a little over stock if you use good gas. You'll gain a few ponies as well as a slightly higher idle. In the end, the ECU will monitor idle speed and is supposed to raise/lower it according to demands such as power steering drag, a/c compressor drag, etc.

700RPM would be close to normal warm idle with no accessories or a/c running.

moshlub

Why would you want to raise your idle?

Like SC300T said ... I don't believe you can change your idle. If I am correct, the computer is responsible for controlling your idle. I had an older Nissan (1985) that had a screw that seemed to change the idle. But once the computer took over, the idle went back to where it was before. Even if you find something that will increase your idle, the computer system will change it right back.

933005spd

Deceptik is correct in asking why? My 300 also idles low, but it is not a problem. Do you experience issues such as hesitation, shut off or rough idle at the low speed?

Deceptik1

iTrader: (6)

What is the idle supposed to be at. The reason I am asking is becaue I thought 700rpm is pretty low when there are no accessories turned on. So when those accessories such as lights, stereo, heater, etc are on I'm afraid the idle will go below 700rpm and not charge the battery or shut off but since its seems thats the normal idle I won't worry.

willard west

Is somewhere in the deep dark recesses of the mind of the programming nerd who wrote the ECU program. Your engine ECU will automatically control the engine RPM to cpmpensate for A/C, steering loads, etc.

LEXUSver

'92 Lexus SC300 A/T with TRAC. You will need a 9mm box wrench and an allen wrench. The feeler gauge is inserted between the end of the setscrew and the throttle lever. It is normally sealed with a nail polish but useful during troubleshooting such as low or high idle rpm.

Nelexus88

Even if you manage to increase the idle speed in some manner, the computer will likely throw a CEL light because it is not idling at the programmed speed.