WHERE IS LOCATED THE KNOCK SENSOR AND IDLE AIR CONTROL VALVE - NISSAN ALTIMA 98

Have you ever run out of oil? Do you change the oil and filter regularly? That sounds like big end bearings knocking.

Knock Sensor location in the link.

https://www.google.com/search?q=2005+nissan+altima+3.5+knock+sensor+location

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Lots of early Nissans had a fuel feed pipe problem The plastick pipe split causing fuel starving engine missing

Could be a dirty throttle body, vac leak, or a defective idle air control valve. The computer adjusts idle speed by controlling the amount of air entering the throttle body via the control valve.
Is the check engine light on ?

An IAC (idle air control) motor is designed to adjust the engine idle RPM speed by opening and closing an air bypass passage inside the throttle body. The cars computer or PCM (powertrain control module) receives information from various sensors and will output signals to adjust the idle air control motor in or out to adjust engine idle speed by controlling engine idle air. An idle air control motor can fail one of two ways, either the motor short circuits and stops working or the motor will develop high resistance and cause the idle air control motor to react slowly, either failure can cause the engine to stall at idle. When a trouble code scan is performed it sometimes won't always detect a failed or weak idle air control motor.

remove the ignition control module on top of mass air flow sensor,apply heat sink to transistor,and reinstall then change spark plugs, wires,distributor cap,and rotor,remove air intake,and clean out throttle body port with carbon cleaner,check ignition coil for lump(defective) and check pcv valve to see if it's stuck wich is located on a breather seperator on top of the idle air control valve......also,check 75 amp fusible link for battery under hood on drivers side...........in the same compartment,look for the 10 amp fuse to the alternator..........follow these instructions,and your car will run excellent.....nissan altima master 1993-1997 10 years owning a 1994 altima............been there done that.................it does not get any better than that trust me..........total money to spend should be about $120.00 dollars...........peace..........

Is the car idling high? It sounds like air control valve has gone bad..just a though. I know when a car isn't idling right, its usually that idle air control valve or a vacuum leak

Although it could be any number of things you may want to start with the air filter, a dirty air filter restricts the airflow to the engine and can cause exactly what you have described.

3 other suspects could be, Idle air control valve, mass airflow sensor, or throttle position sensor.

change ur Airflow sensor buddy. thats the only problem. And if yet it doesnt work then check ur crank sensor....

It is where the dashed circle is at the end of the line...


Email me at [email protected] for a larger pic....we can't post them that large here.

Removal and Installation To Remove:

1. Remove or disconnect the following:
   • Mass air flow sensor electrical connector
   • Tube clamp at the electronic throttle control actuator
   • Air cleaner to electronic throttle control actuator tube, upper air cleaner case
   • Mass air flow sensor from the cleaner case.

To Install:

1. Install or connect the following:
   • Mass air flow sensor to the cleaner case
   • Air cleaner to electronic throttle control actuator tube
   • Tube clamp at the electronic throttle control actuator
   • Mass air flow sensor electrical connector