I have a 1996 nissan sunny fuel injected ... i have changed the plugs, injector rail, distributer, throttle body, and my engine is still misfiring can some one advise me please..

buy it like this or just happened now,? or ?
when did car last run great? is/was it a daily driver? or a hanger queen.? (old fuel does not burn good)
no engine told and is a full on engine question. 4 engines used just in USA.
there are 50 causes of any engine/EFI be misfiring or sluggish
bogging , lack of engine power.
do a real turn-up first? all filter (air /fuel) spark plugs and HP spark wire sets.
Distributor cap and rotor and wire sets do not ever last 28 years
it is tuneup listed item nor do that HV wires last 28 years

SLUG mode.
engine compression good , over 150PSI all.
spark good. covered above)
last is fuel , pressure at spec.
FPR on fuel rail bad?, , vast are this OLD./
injectors clogged
the injector leak down test fails
the injector is in the throttle body here TBI injection is is called
and these injectors clog for SURE if ran bad fuel.
I can name 20 tests to do. any shop knows how.
but many shops now, the tech there never saw any TBI before.
if CEL lamp is on running , there are DTC flash error codes to find.

Very few cars 1995 are on the road and may are parked and with bad fuel in the tank or tank full of rust or both

Look.
If you see a fuel rail or a short-throat throttle body, it is fuel injected.
If you see a carburetor... well, I think you get the point :)
From the year (unless it is a non-U.S. model), it is most likely FUEL INJECTED.

THROTTLE POSITION SENSOR, MISFIRE, #4 MISFIRE, KNOCK SENSOR, THESE ARE YOUR TROUBLE CODES, PO120,PO300, PO304, PO325, RESPECTIVELY, REPLACE THE TPS @ THROTTLE BODY, REPLACE KNOCK SENSOR , @ ENGINE BLOCK, REPLACE YOUR SPARK PLUGS & PLUG WIRES ! AND YOU MUST ALSO REPLACE BOTH YOUR AIR & FUEL FILTERS, DISTRIBUTOR CAP & ROTOR , INSPECT, MAY NEED TO REPLACE, I WOULD ANYWAY !!!!!!!! ADD SOME GOOD FUEL INJECTOR CLEANER TO TANK, NEXT FUEL UP !

Is there a crank sensor, if so that would be my first check.

so that mean the old one is all ready removed.?
or did you mean all steps in the fsm for INJECTOR.
the steps are the same on all EFI fuel rail injectors.
you could google that or you tube it or read the FSM.

hide call keys from step 2 on, or very bad things can happen.
(wife or kids no aware of danger)
ill just cover the (basics)
1: per FSM , depressurize the system, in can be at 60PSI
parked. so avoid fuel in eyes, or a fire. we do that first.
gain access to rail under failure. (RUF) (no barking)
2: remove injector X , wire plug. (failing)
3: then detach the injector rail clamps the both rails off as one....
injector are all now loose, to pull off.
4: add new seals to new injector, and install in reverse order.

that's it, only the gain access , varies,... mostly.

last depressure steps:
run engine,
remove fuel pump relay, engine stalls. key off, hide keys!

next tje FSM words (just the OFF section)

1. Remove fuel tank filler tube cap.
2. Perform Fuel System Pressure Release Procedure.
3. Remove negative battery cable at battery.
4. Remove air duct at throttle body air box.
5. Remove air box at throttle body.
6. Disconnect fuel line latch clip and fuel line at fuel rail. A special tool will be necessary for fuel line disconnection.
7. Remove necessary vacuum lines at throttle body.
8. Disconnect electrical connectors at all 6 fuel injectors. Push red colored slider away from injector. While pushing slider, depress tab and remove connector from injector. The factory fuel injection wiring harness is numerically tagged (INJ 1, INJ 2, etc.) for injector position identification. If harness is not tagged, note wiring location before removal.
9. Disconnect electrical connectors at throttle body sensors.
10. Remove 6 ignition coils.
11. Remove 4 fuel rail mounting bolts.
12. Gently rock and pull left side of fuel rail until fuel injectors just start to clear machined holes in cylinder head. Gently rock and pull right side of rail until injectors just start to clear cylinder head holes. Repeat this procedure (left/right) until all injectors have cleared cylinder head holes.
13. Remove fuel rail (with injectors attached) from engine.

end expert.

alldata.com
login and read all steps. that be best , then ask questions?

FUEL INJECTION THROTTLE BODY INJECTION SYSTEM HAS TWO ROUND FUEL INJECTORS ON TOP.CARBURETOR DONT HAVE FUEL INJECTORS.IT HAS CHOKE VALVE AND FUEL NOZZLE WHICH IS THE FUEL METERING SYSTEM.

This truck has 2 ignition shstems,One of the modules is malfunctioning. follow the primary wiring from distributor to the ignition modules closeby. Disconnect one at a time untill problem found.

Is the car fuel injected? you sure it doesn't have throttle body injection? if it is point injection you will see the silver fuel rail right on top of the engine, going into the head. If it's throttle body it will only have 1 injector on top of the carb(or throttle body).

I respectfully disagree.
A P-0300 will NOT be set in a Corolla by a dirty fuel filter.
Replacing the fuel filter could be a very costly operation, as I have observed that the fuel line threads that connect to the fuel filter easuily get damaged when removing the fuel filter.

In short, don't replace the filter until you are SURE that it is the culpit.
In this case, the fuel filter is NOT the culprit..
Save your money; and your time.
Additionally, premium fuel does not clean fuel injectors. That expense would be a waste of money. The engine will actually run WORSE on premium fuel; the engine is NOT designed to run on premium. 87 or 89 (better choice/89) is the grade to use.

If you really want to track down the P-0300 code, which is a multiple/random cylinder misfire, I would look at the quality of the fuel in the car; ie water in the gas. Second, I would remove the plugs and examine them closely. A worn center electrode will also set the P-0300 code, as will bad/weak plug wires (over 5 years old).

Please feel free to contact me back if you need further assistance. Thanks for choosing FixYa for assistance.

i have a nissan b-14 idle roughly sometimes cut off when in traffic. any solutions???????