How do you adjust idle 1996 4 cylinder Toyota Camry?

Answer 1

Idle speed is computer controlled in most fuel injected engines. The computer knows the speed the engine is turning and what it 'should' be turning and adjusts an idle speed solenoid or valve accordingly. Assuming the engine is in good condition there are a couple of easy to fix reasons your idle could be off. If the idle is too high that control valve could be dirty or bad. If it's too low then a frequent reason is a dirty throttle body.

If you've never cleaned the throttle body in the area around the butterfly that controls air intake take a close look with a flashlight. You'll probably notice a thin ring of carbon around the area where the butterfly contacts the throttle body. To clean it, hold the butterfly open while you use some fuel injector (or carb) cleaner and a toothbrush. Get the carbon ring out and chances are pretty good your idle will be back to normal.

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