QuestionQUESTION: Hi,i have my nissan 97 series 3, all power, manual trans. The RPM drops when i stepped in the clutch in sudden stop, the engine will die and I will restart again. This happen when the aircon is ON only. Sometimes it RPM drops up to 1rpm, its rattles but goes up again. Some mechanos told me, my servo had to be cleaned. I am hesitant to have my servo clean. Because the RPM is okay when aircon is OFF and ON while on neutral and running. What is the really the trouble?
ANSWER: Ronaldo,
The idle air control valve, the manifold absolute pressure sensor or a dirty throttle body are the most common suspects for the problem you describe. The computer cannot keep up with the sudden drop in RPMs.
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QUESTION: Thank u Sir. Is cleaning the servo will solve the problem? What parts will I replace?
ANSWER: Ronaldo,
Clean the throttle body first. After that, if it does not solve the problem, change the idle air control valve. Email me back with what you find.
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QUESTION: Sir, the throttle body is already cleaned. But the problem is still there. They found out that the sensor switch connected to the a device that controls the air of the aircon has no current of power. The mechanic told me thats the reason why my RPM is goes down when ever I stepped on the clutch and also why RPM downs when the aircon thermastat is ON. They told me the sensor swith is connected to the computer box. It need to track dwon why it has no electric current.
AnswerRonaldo,
The air conditioner provides signal to the ECM to increase RPM to compensate for the extra load. I would have the technician verify, since the compressor applies. I would think the idle air control valve is not working properly since the car idles normally at other times. Remove yours and clean it and possibly replace it.
