I replaced the air flow sen, then checked thefuel presure its good, what else could cause it not to run right

Anand Kumar

• 2035 Answers
• Posted on Oct 13, 2008

SOURCE: IGNITION FAILURE ON 280 ZX (82)

1. Turn the ignition switch OFF. Disconnect the fusible link connector for the fuel injection wiring harness. Be sure the ignition is OFF before doing this. Disconnect the cold start valve wiring harness connector. Disconnect the high tension lead (coil-to-distributor) at the distributor and hold it 0.13-0.25 in. (3.3-6.3mm) away from the cylinder head with a pair of insulated pliers and a heavy glove. When the engine is cranked, a spark should be observed. If not, check the lead and replace as necessary. If there is still no spark, go on with the following system checks.
   1. Make a check of the power supply circuit. Turn the ignition OFF. Detach the connector from the top of the IC unit. Turn the ignition ON. Measure the voltage at each terminal of the connector in turn by touching the probe of positive lead of the voltmeter to one of the terminals and touching the probe of the negative lead of the voltmeter to a ground, such as the engine. In each case, battery voltage should be indicated. If not, check all of the wiring, the ignition switch and all connectors for breaks, corrosion, discontinuity etc., then repair as necessary
   2. Check the primary windings of the ignition coil. Turn the ignition OFF. Detach the harness connector from the negative coil terminal. Use an ohmmeter to measure the resistance between the positive and negative coil terminals. If resistance is 0.84-1.02 ohms, the coil is OK; replace it if the reading is far from this range.
2. If the power supply, circuits, wiring and coil are in good shape, check the IC unit and pick-up coil as follows:
   1. Turn the ignition OFF.
   2. Remove the distributor cap and ignition rotor.
   3. Using an ohmmeter, measure the resistance between the two terminals of the pick-up coil, where they attach to the IC unit. Measure the resistance by reversing the polarity of the probes. If approximately 400 ohms are indicated, the pick-up coil is OK, but the IC unit is bad and must be replaced.

1. If the resistance is other than 400 ohms, proceed with the following:
   1. Be certain the two pin connector to the IC unit is secure.
   2. Turn the ignition ON.
   3. Measure the voltage at the ignition coil's negative terminal.
   4. Turn the ignition OFF.

1. If 0 voltage is indicated, the IC unit is bad and must be replaced.

1. If battery voltage is indicated, remove the IC unit from the distributor, by proceeding as follows:
   1. Disconnect the battery ground (negative) cable.
   2. Remove the distributor cap and ignition rotor.
   3. Disconnect the harness connector from the top of the IC unit.
   4. Remove the two screws securing the IC unit to the distributor.
   5. Disconnect the two pick-up coil wires from the IC unit.

1. Remove the IC unit.

1. Measure the resistance between the terminals of the pick-up coil. It should be approximately 400 ohms. If so, the pick-up coil is OK and the IC unit is bad. If the resistance is other than 400 ohms, the pick-up coil is bad and must be replaced.

SOURCE: 01 nissan pathfinder

The mass airflow can get dirty and you will get trouble codes for everything under the hood except for the mass airflow. Try unplugging your mass airflow and driving the vehicle, if your problem goes away you need to clean the sensor. Buy some mass airflow cleaner though because other cleaners can damage the coating on the sensor.

SOURCE: 000 NISSAN Xterra -- after warming up, loses RPM by 500-1000..... have replaced ignition wires and distributor, checked mass air flow sensor and OK.....

I had a problem on my Nissan Xterra 2000. Symptons sound similar. In my case, it ran fine for a while and then suddenly the engine starts to stumble and lose output. At one point it did not even have enough HP to move. Irregular idling too. Thought it was water in my fuel. Bought water remover from the store and added to gas tank. Problem did not go away. Instead, "Service Engine Soon" light came on. Had to have it towed to the dealer as there was no way the engine could keep up with traffic. Dealer replaced the "Crank Position Sensor" today. Parts $33.00, Labor: $300 (about 3 hrs worth of work). Seems to work fine now but I will wait and see. Dealer also stated that Distributor bearing appears to be noisy and will need to be replaced sooner or later. I will wait for it to go before I fix that.

SOURCE: i have 96 Nissan Sentra GXE standard. It starts

check spark plugs

SOURCE: '93 D21 ka2.4. miss fire,surge, and runs rich

sounds like you have a very dirty mass air flow meter. invest in a new one and be sure to clean the throttle body with an appropriate cleaner and tooth brush.