02 bmw745I I replace the spark plugs twice and coils twice. I still cant get rid of the code p1343 misfire at cylinder 1 with fuel cut-off. I ALSO REPLACE THE FUEL INJECTORS HELP ME.

There is no p3100 code!!

I think you copied this wrong. the code is p0301, which is a common one.

The P0301 code means that the cylinder 1 is misfiring or is randomly misfiring. Start by checking for intake leaks an if no leaks are found the next step is to replace the spark plugs on cylinder 1. If the problem persist more tests needs to be done to diagnose problem.

Possible causes
- Faulty spark plug 1
- Clogged or faulty fuel injector 1
- Faulty ignition coil 1
- Fuel injector 1 harness is open or shorted
- Fuel injector 1 circuit poor electrical connection
- Ignition coil 1 harness is open or shorted
- Ignition coil 1 circuit poor electrical connection
- Insufficient cylinder 1 compression
- Incorrect fuel pressure
- Intake air leak

Most likely cause:
Faulty spark plug 1 or Faulty ignition coil 1 (Ignitor coil)

Either are easy fixes. Start with a new spark plug. If the problem continues replace the coil. Pic below. new about $30-$40.

replace the coil,it is misfiring

The car needs carlibration,the code means random cylinder misfire.fuel line need and MAF need check

Hi Jason:
A Random/Multiple Cylinder Misfire Detected unfortunately doesn't tell you specifically which cylinder(s) is/are mis-firing, nor why.

A code Random/Multiple Cylinder Misfire Detected may mean that one or more of the following has happened:
Faulty spark plugs or wires
Faulty coil (pack)
Faulty oxygen sensor(s)
Faulty fuel injector(s)
Burned exhaust valve
Faulty catalytic converter(s)
Stuck/blocked EGR valve / passages
Faulty camshaft position sensor
Defective computer

Possible Solutions:
If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.

If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.

Random misfires that jump around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open.

Hope this helps; also keep in mind that your feedback is important and I`ll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using FixYa, have a nice day.

As of 1996,all cars sold in the US were required to have an OBD-II computer interface port.
You may want to go to Advance Auto Parts, AutoZone, or Pep Boys, and get a free read
of the code(s) that you computer may be posting to help with your diagnosis.

The code coming from your vehicle's computer may be one or more of:

P0130 02 Sensor Circuit Malfunction (Bank I Sensor 1)
P0131 02 Sensor Circuit Low Voltage (Bank I Sensor I)
P0132 02 Sensor Circuit High Voltage (Bank I Sensor 1)
P0133 02 Sensor Circuit Slow Response (Bank 1 Sensor 1)
P0134 02 Sensor Circuit No Activity Detected (Bank I Sensor 1)
P0135 02 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
P0136 02 Sensor Circuit Malfunction (Bank I Sensor 2)
P0137 02 Sensor Circuit Low Voltage (Bank I Sensor 2)
P0138 02 Sensor Circuit High Voltage (Bank I Sensor 2)
P0139 02 Sensor Circuit Slow Response (Bank 1 Sensor 2)
P0140 02 Sensor Circuit No Activity Detected (Bank 1 Sensor 2)
P0141 02 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0142 02 Sensor Circuit Malfunction (Bank I Sensor 3)
P0143 02 Sensor Circuit Low Voltage (Bank I Sensor 3)
P0144 02 Sensor Circuit High Voltage (Bank I Sensor 3)
P0145 02 Sensor Circuit Slow Response (Bank 1 Sensor 3)
P0146 02 Sensor Circuit No Activity Detected (Bank I Sensor 3)
P0147 02 Sensor Heater Circuit Malfunction (Bank I Sensor 3)
P0150 02 Sensor Circuit Malfunction (Bank 2 Sensor I)
P0151 02 Sensor Circuit Low Voltage (Bank 2 Sensor I)
P0152 02 Sensor Circuit High Voltage (Bank 2 Sensor 1)
P0153 02 Sensor Circuit Slow Response (Bank 2 Sensor 1)
P0154 02 Sensor Circuit No Activity Detected (Bank 2 Sensor 1)
P0155 02 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1)
P0156 02 Sensor Circuit Malfunction (Bank 2 Sensor 2)
P0157 02 Sensor Circuit Low Voltage (Bank 2 Sensor 2)
P0158 02 Sensor Circuit High Voltage (Bank 2 Sensor 2)
P0159 02 Sensor Circuit Slow Response (Bank 2 Sensor 2)
P0160 02 Sensor Circuit No Activity Detected (Bank 2 Sensor 2)
P0161 02 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
P0162 02 Sensor Circuit Malfunction (Bank 2 Sensor 3)
P0163 02 Sensor Circuit Low Voltage (Bank 2 Sensor 3)
P0164 02 Sensor Circuit High Voltage (Bank 2 Sensor 3)
P0165 02 Sensor Circuit Slow Response (Bank 2 Sensor 3)
P0166 02 Sensor Circuit No Activity Detected (Bank 2 Sensor 3)
P0167 02 Sensor Heater Circuit Malfunction (Bank 2 Sensor 3)

Note: "Bank 1" is the side of the engine with cylinder 1. "Bank 2" is the other side.

P0300 - Random/Multiple Cylinder misfire detected
P0301 - Cylinder 1 misfire detected
P0302 - Cylinder 2 misfire detected
P0303 - Cylinder 3 misfire detected
P0304 - Cylinder 4 misfire detected
P0305 - Cylinder 5 misfire detected
P0306 - Cylinder 6 misfire detected
P0307 - Cylinder 7 misfire detected
P0308 - Cylinder 8 misfire detected
P0313 - Misfire detected with low fuel

Maximas with the VE30DE and VQ30DE engines use a distributorless ignition system that is controlled by the Engine Control Module (ECM). The ECM receives a signal from the crankshaft sensor (the CPS - Crankshaft Position Sensor), and processes the signal based on inputs
from other various engine sensors, including the Oxygen sensor.
(this is the role of the O2 sensor in ECM operation).
Then the ECM sends signals to each of the individual coils in the proper firing order.
This system is more efficient than a distributor, and has fewer moving parts. The high voltage coils are directly attached to each spark plug, allowing a higher energy spark within the cylinder. A high energy spark means a faster, more thorough burning of the air/fuel mixture, which produces more power and lower emissions.


SECONDARY SPARK TEST - works for all cars, including Maxima.


1. Remove the spark plug.

2. Install the spark plug to the ignition coil/coil pack, then attach the coil wiring.

3. Ground the plug at a good ground location on the engine.

4. Crank the engine and check for spark.

5. If spark occurs, the ignition system is functioning properly.

6. If no spark exists, test the ignition coil/coil pack, power transistor and related wiring.

----------------------------------------------------------------------------------------------------------------------------
HEI Ignition Spark test - works for all cars, including Maxima.

The next level test you may want to try is a HEI (high energy ignition) spark tester kit. Cost is
about $30 at most auto parts stores. Harbor Freight Tools sells a chinese equivalent for about $16.
Place the spark tester on each of the spark plugs, and watch as the little light in the tester will
light up each time the spark plug is fired by the computer. You can actually see weak or
intermittent sparking as the motor runs - you can tell by the relative strength of the light as
you compare the intensity and duration of the light across all 6 cylinders.

If your problem were the alternator (or its built-in voltage regulator), your battery would not be
getting a proper charge, and you
wouldn't be able to start the car after a drive, since the battery would have been drained during the
drive - normally, the alternator will both charge the battery and run all electrical
features of the car during a drive.

To test your alternator, place your DMM (digital multimeter) across the battery terminals while the
car is running - it should read 13.5VDC to 14.5VDC. With the car off, you can test your battery
voltage with the same DMM - it should read 12.65 VDC (for a fully charged battery).

Alternatively, you can take your car to Advance Auto Parts, AutoZone, or Pep Boys, and they'll
attach their "charging system tester" to your car and give your car a nice test for free.
I do this with my customers' cars just to get that nifty printout of the problem. Its nice
to show a vehicle owner somethng in black & white when I'm recommending a new charging
or ignition system component (some of which can be a bit pricey).

P0301 - Cylinder 1 Misfire Detected.

Possible Causes:
- Improper spark plug at cylinder #1
- Insufficient compression at cylinder #1
- Incorrect fuel pressure
- The injector circuit is open or shorted at cylinder #1
- Fuel injector #1 may be faulty
- Intake air leak at cylinder

Possible Solutions:
- Perform Injector Service
- Replaced Spark Plug #1
- Replaced Injector #1
- Replaced Ignition Coil #1

Being you have a heavy gas smell I would look into the injectors. If injector #1 is over producing it can cause a misfire. Test your compression and fuel pressure.

P0301 - Cylinder 1 Misfire Detected.

Causes:
- Improper spark plug at cylinder #1
- Insufficient compression at cylinder #1
- Incorrect fuel pressure
- The injector circuit is open or shorted at cylinder #1
- Fuel injector #1 may be faulty
- Intake air leak

Solutions:
- Perform Injector Service
- Replaced Spark Plug #1
- Replaced Injector #1
- Replaced Ignition Coil #1

P0303 - Cylinder 3 Misfire Detected.
Follow info from P0301.

P0316 - Misfire Occurred In The First 1,000 Engine Revolutions.

Causes:
- Damaged CKP sensor.
- Ignition System.
- Fuel Injectors
- Running out of fuel
- Fuel Quality
- Base engine
- Damaged Powertrain Control Module

Solutions:
Usually the P0316 is combine with a P03XX codes. The P03XX code indicates in which cylinder the misfire occurred.

P0300 - Random / Multiple Cylinder Misfire Detected

Possible Causes:
- Improper spark plug
- Insufficient compression
- Incorrect fuel pressure
- The injector circuit is open or shorted
- Fuel injectors may be faulty
- Intake air leak

Possible Solutions:
- Perform Injector Service
- Replaced Spark Plugs
- Replaced Injectors
- Replaced Ignition Coils

P0301- Cylinder Number 1 Misfire Detected

Possible Causes:
- Improper spark plug at cylinder #1
- Insufficient compression at cylinder #1
- Incorrect fuel pressure
- The injector circuit is open or shorted at cylinder #1
- Fuel injector #1 may be faulty
- Intake air leak at cylinder

Possible Solutions:
- Perform Injector Service
- Replaced Spark Plug #1
- Replaced Injector #1
- Replaced Ignition Coil #1

Most likely your issue is with cylinder number 1. Follow the info I have provided and you should be able to solve this issue.

P0300 Random Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0302 Cylinder 2 Misfire Detected
P0303 Cylinder 3 Misfire Detected
according to this fault codes first mark ignition coils
3 ---------------- 6
2 ---------------- 5
1 ---------------- 4
RB-------------LB
this right banks and left bank, please remove Ignition coils with lids and spark plugs from right bank and swap with left bank, if fault code change as
P 0304 Cylinder 4 Misfire Detected
P 0305 Cylinder 5 Misfire Detected
P 0306 Cylinder 6 Misfire Detected
You can Identify it's a faulty ignition system then next swap ignition lids from ignition coils be careful each coils have two lids one short and other long bit deference and when you remove and fix it to the car keep in mind correct order because each coil two different fire for two spark plugs don't mix up, if you mix it can create the fault code.if you detect any fault ignition coils or spark plugs or lids replace that and also whether god or bad recommend to replace spark plugs, find the right that's most important thing, if this way couldn't found the any ignition fault next step is check fuel presser, when the engine running fuel presser must be around 4.5 bar without engine running must be 4 to 6 bar if the fuel presser too low need to check two different things one is fuel pump other is fuel injectors, in this case you can swap injectors from right bank to left bank and find is the injectors leaking, if not leaking faulty fuel pump.is this information helped you? if yes please leave a comment,

misfire :-------- try checking your 02 sensors /fuel pump and filter.

for 51 cylinder misfire :---
Change the coil. Period. Very easy to remove from the vehicle if it's a 4 cyl. Follow that spark plug wire from the spark plug to the other end. What it's attached to you should replace
for 54 cylinder 5 misfire :---First you have to eliminate the most obvious problems, like spark plug and spark plug wire. If you replace those and you still have a misfire, then it's a good idea to look for a vacuum leak in the intake manifold