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Testing a No Start-No Spark or a Misfire Condition on your Nissan Mini-Van or Pick Up or SUV or the Mercury Villager (with the 3

Testing a No Start-No Spark or a Misfire Condition on your Nissan Mini-Van or Pick Up or SUV or the Mercury Villager (with the 3.3L V6 engine) is not difficult at all. No expensive tools or diagnostic equipment is needed, and this article will show you just how to do it step by step.

With the tests in this article, you'll be able to test and diagnose: A BAD power transistor, or a BAD ignition coil, or a BAD distributor cap, or BAD spark plug wires on your Nissan vehicle.

On the box titled ‘Applies To’ on the right column, you'll find a complete list of Nissan and Infiniti models that this test article applies to.

Prueba del Módulo y Bobina de Encendido 3.3L Nissan (1996-2004) INCLUDEPICTURE "http://easyautodiagnostics.com/templates/blue_wrench_10/images/es-flag.gif" \* MERGEFORMATINET

Puedes encontrar este tutorial en Español aquí: (en: autotecnico-online.com).

Symptoms of a BAD Transistor, Ignition Coil, Spark Plug Wires, or Dist. Cap

If you're Nissan SUV or mini-van is suffering a Misfire... the check engine light (CEL) will be on to let you know that YES, there really is something wrong. Here are a couple of other symptoms your vehicle may experience with a Misfire Condition:

1. Diagnostic trouble codes (DTC) stored in the computer's (PCM) memory:

· P0300, P0301, P0302, P0303, P0304, P0305, P0306

2. Misfire that does not light up the check engine light (CEL).

3. No power.

4. Idles rough.

5. BAD gas mileage.

6. Black smoke coming out of the tail-pipe.

7. Rotten egg smell coming out of the tail-pipe.

8. Smell of unburned gasoline coming out of the tail-pipe.

9. Won't pass the state emissions test.

If the power transistor or the ignition coil is BAD, then the most common symptom is that your vehicle will CRANK but not START and there will be no spark at any of the spark plug wires.

Basic Nissan Ignition System Theory

To be able to successfully diagnose a Misfire or No Start on your Nissan vehicle (whether it’ a pick up, SUV, or a mini-van) it'll help to know how spark is created and fed to the engine cylinders. This is what happens in a nutshell when you turn the key and crank the engine:

1. The crankshaft position sensor and camshaft position sensors start to generate and feed their signals to the vehicle's PCM (Powertrain Control Module=Fuel Injection Computer).

2. The PCM uses these signals to know where each piston is at in relation to its combustion cycle and with this info, the PCM knows when to start activating the power transistor, the fuel injectors and a host of other things to get your Nissan vehicle started.

· The power transistor is the ignition control module (ICM) in the Nissan vehicles.

· The power transistor is located within the distributor assembly and is part of the cam sensor assembly.

3. So then, after receiving the crank (CKP) and cam (CMP) signals, the PCM sends the power transistor a Triggering Signal that tells the power transistor exactly when to activate the ignition coil.

4. The power transistor activates the ignition coil by opening and closing the Primary Current Circuit of the ignition coil... and as you may already be aware it's this opening and closing action that makes the ignition coil spark away.

5. The spark created by the ignition coil is fed to the distributor rotor directly by the distributor cap and then from there to each engine cylinder via a spark plug wire.

With the simple and easy tests presented in this test article you'll be able to find the exact cause of your Nissan vehicle's Misfire or No Start Condition (if it's ignition system related) and in the process save time and money.

Power Transistor Test and Ignition Coil Test 3.3L Nissan (1996-2004)

17 November 2010

  Updated: 02 March 2015

  Written by: Abraham Torres-Arredondo

  Article Id: 389

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· Page 6

What Tools do I Need to Test the Ignition System?

Although the tests in this article are easy and simple, you do need some specific tools to perform them with. Here's the list:

1. An HEI spark tester

· This inexpensive spark tester is a MUST have tool to be able to correctly diagnose the ignition system on your Nissan vehicle with the info and tests in this article (don't have an HEI spark tester? Need to buy one? You can buy it here: OTC 6589 Electronic Ignition Spark Tester

INCLUDEPICTURE "http://ir-na.amazon-adsystem.com/e/ir?t=easyautodiagn-20&l=as2&o=1&a=B0050SFVO2" \* MERGEFORMATINET ).

Don't use a regular spark plug instead of a spark tester.

2. Battery jump start cables.

3. A digital multimeter that can read Hertz (Hz) frequency.

· Without a multimeter that can read Hertz frequency, you won't be able to accomplish some of these tests. (don't have a digital multimeter that can read Hertz frequency? Click here to see my recommendations: Buying a Digital Multimeter for Automotive Diagnostic Testing).

4. A helper.

· You'll need someone to help you crank the engine while you perform the tests in the engine compartment.

5. A repair manual.

· For whatever remove and replace info you'll need that is not covered by this article.

Power Transistor/Cam Sensor Assembly Circuit Descriptions

There are 6 wires coming out of the main distributor connector. This connector connects to the power transistor/cam sensor assembly that's located within the distributor.

Now, don't worry, you don't need to test all of them to diagnose this ignition system. Below are the circuit descriptions of all six wires (circuits):

· Circuit labeled 1

· Triggering Signal for Power Transistor. This Signal comes from the PCM.

· Circuit labeled 2

· Ground Circuit for the Power Transistor.

· Circuit labeled 3

· Camshaft Position Sensor Signal - 120° REF Signal.

· Circuit labeled 4

· Camshaft Position Sensor Signal -1° POS Signal.

· Circuit labeled 5

· Camshaft Position Sensor Power (12 Volts).

· Circuit labeled 6

· Camshaft Position Sensor Ground.

Ignition Coil Circuit Descriptions

The other connector has two wires coming out of it and both of these go directly to the ignition coil inside of the distributor. Here are their circuit descriptions:

1. Circuit labeled 1

· Power (12 V) Circuit.

2. Circuit labeled 2

· Switching Signal output to the PCM.


· 1

· 2

· 3

· 4

· 5

· 6

TEST 1: Testing for Spark at the Spark Plug Wires

The starting point of your Misfire or No-Start diagnosis is testing for spark at the spark plug wires. Now, you might already have a specific cylinder you want to test first (if you have a specific Misfire Diagnostic Trouble Code: P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308) or you just don't know where to start. Well, my recommendation is to test all of the spark plug wires for spark regardless.

I want to stress the importance of using an HEI spark tester to perform all of the spark tests. Here are a couple of other important suggestions:

1. Do not use a regular spark plug in place of a spark tester.

2. Do not pull the spark plug wire off of its spark plug while your helper cranks the engine to verify spark. This will damage the ignition coil, if it isn't fried already.

OK, here we go:

1. Disconnect the spark plug wire from its spark plug.

2. Attach the HEI spark tester to the spark plug wire.

3. With a battery jump start cable, attach the HEI spark tester to a good ground point or to the battery negative terminal.

4. Have your assistant crank the engine while you eye-ball the spark tester. If you're testing a Misfire Condition, the engine will start... so be careful.

5. Repeat the test for all of the remaining spark plug wires (if applicable).

6. You're going to see only one of two results: either spark jumping across the HEI spark tester's air gap or No spark.

CASE 1: If you got spark on all of the spark plug wires: This results let's you know that the power transistor, ignition coil, distributor rotor and cap are OK. Having all of the spark plug wires firing off spark eliminates all of these components as the cause of your Misfire Codes or No Spark- No Start Condition. For some suggestions as to what could be the cause of the misfire condition and/or Misfire Codes, go to TEST 8.

CASE 2: If you got NO spark from any (none) of the spark plug wires: The next step is check that the ignition coil is creating and feeding spark to the distributor cap. You'll accomplish in TEST 3. Go to TEST 3.

CASE 3: If you got spark on some but not all of the spark plug wires: The next step is check for spark directly on the distributor cap towers that feed spark to these wires that did not fire off spark. Go to TEST 2.

TEST 2: Testing for Spark at the Distributor Cap

It's not uncommon for a distributor cap to have one or more towers not transmitting spark from the distributor rotor to their respective spark plug wires. This problem, of course, this will cause a misfire condition.

This type of problem can be tested with a simple spark test. In this test step, you'll be testing for spark with the HEI spark tester directly on the distributor cap tower (or towers) whose spark plug wire did not fire