Ok first check to see if there are any codes stored in the computer.Heres how.
Heres how to get codes.Let me know if there are any codes stored.
How to pull ECU error codes for 87-95 Pathfinders and hardbody pickups:The ECU is under your passenger's side seat. You can gain access to it by simply sliding the seat all the way forward and removing the plastic cover from the ECU. You can also remove the seat if you want, it makes access a little easier.The early VG30E and VG30i ECU's have a tiny toggle switch on the side of the ECU with a small snap-in switch cover that must be utilized to select the diagnostic mode of the ECU. The 4-cylinder ECU has a slotted switch that turns 1/4 or 1/2 turn clockwise and counterclockwise to do the same task. Pictures: This is the ECU from my very dirty (and wrecked) 89 VG30i Pathfinder. VG30E ECU's have a slotted round switch in the same place as the toggle switch.Seat removed; ECU in place on the floor with cover. The cover has ONE screw holding it down. Remove that and the cover will pull off.Diagnostic selector switch with switch cover removed and set on top of the ECU.This is where the LED lights are visible on top of the ECU.For 4-cylinder:1. Turn the ignition switch on, but do not start the engine. All of the lights in the dash should be on.2. Turn the 'diagnostic mode selector' screw on the ECU fully clockwise. The check engine light will go out. Wait 5 seconds, then turn the screw fully counter clockwise.3. The check engine light will then begin to flash the trouble code. (number of long flashes is the 1st digit, number of short flashes is the 2nd digit)4. To clear all stored codes and turn the check engine light off, turn the screw fully clockwise while it is in diagnostic mode. Wait 5 seconds, then turn the screw fully counter clockwise.5. To keep the codes stored, simply turn the key off as the check enginelight is flashing and the ECU will keep all stored codes and the check engine light will remain on.For V6:1. Turn the ignition switch on, but do not start the engine. All of the lights in the dash should be on.2. There is a little plastic tab you pull off of the side of the ECU(facing the door). A small toggle switch is behind it with 2 positions, "ON" and "DIAGNOSTICS". Using a small screwdriver or tool, move it to the diagnostics position. The red and green LED's on top of the ECU will blink simultaneously. One time, pause, then 2 times, three times, pause...so on for each mode, 1 through 5. Mode 3 is the most commonly used mode and will yield the ECU trouble codes you need to figure out what's going on with your engine.3. After it blinks both LED's 3 times move the toggle switch back to the on position. After about five seconds it will start to output out the diagnostic codes as with the 4-cylinder ECU. Note each code as it is displayed, the red LED flashing once for 10's, and the green LED flashing once for 1's. Meaning: One red flash and two green flashes means code 12.4. To clear the ECU of any trouble codes, move the switch to the "DIAGNOSTICS" position then back to the "ON" position and turn off the key.1986.5-1995 Nissan ECU Flash Codes(all engines)11 Crank Angle Sensor/Camshaft Position Sensor.12 Air Flow Meter/Mass Air Flow Sensor.13 Engine Coolant Temperature Sensor.14 Vehicle Speed Sensor.21 Ignition Signal.22 Fuel Pump.23 Idle Switch.24 Throttle Valve Switch.25 Idle Speed Control Valve.28 Cooling Fan Circuit.31 ECM.32 EGR Function.33 Heated Oxygen Sensor.34 Knock Sensor.35 Exhaust Gas Temperature Sensor.36 EGR Control-Back Pressure Transducer.37 Knock Sensor.38 Right hand bank Closed Loop (B2).41 Intake Air Temperature Sensor.42 Fuel Temperature Sensor.43 Throttle Position Sensor.44 ECCS Normal Operation.45 Injector Leak.47 Crankshaft Position Sensor.51 Injector Circuit.53 Oxygen Sensor.54 A/T Control.55 No Malfunction.63 No. 6 Cylinder Misfire.64 No. 5 Cylinder Misfire.65 No. 4 Cylinder Misfire.66 No. 3 Cylinder Misfire.67 No. 2 Cylinder Misfire.68 No. 1 Cylinder Misfire.71 Random Misfire.72 TWC Function right hand bank.73 TWC Function right hand bank.76 Fuel Injection System Function right hand bank.77 Rear Heated Oxygen Sensor Circuit.82 Crankshaft Position Sensor.84 A/T Diagnosis Communication Line.85 VTC Solenoid Valve Circuit.86 Fuel Injection System Function right hand bank.87 Canister Control Solenoid Valve Circuit.91 Front Heated Oxygen Sensor Heater Circuit right hand bank.94 TCC Solenoid Valve.95 Crankshaft Position Sensor.98 Engine Coolant Temperature Sensor.101 Front Heated Oxygen Sensor Heater Circuit right hand bank.103 Park/Neutral Position Switch Circuit.105 EGR and EGR Canister Control Solenoid Valve Circuit.108 Canister Purge Control Valve Circuit