Specifically I'm trying to identify the wire on the spark plug coil assembly to which I should connect the signal wire of a Tachometer to. The wire colours are, red, yellow, green/white, and blue.

1. Connect the distributor's B+ (battery) terminal to a switched 12-volt source, such as the ignition switch.

2. Connect the distributor's tach terminal to the tachometer signal wire, if you have a tachometer.

3. Connect the distributor's ground wire to a good engine ground.

4. Connect the distributor's #1 spark plug wire to the #1 spark plug on the engine. The #1 spark plug is usually located on the driver's side front cylinder.

5. Connect the remaining spark plug wires in firing order sequence to the distributor cap terminals. The firing order for a Buick 455 engine is 1-8-4-3-6-5-7-2.

6. Install the distributor cap and rotor.

Have to connect to ecu to the rpm signal pin

hi.
try ising a differrent plug and wire from the no 2 coil/distributor position (depending on model) to see if it is the wire, or the plug, or the coil/distributor unit.

it is possible to get brand new plugs or wires that are faulty. if another plug and wire still dont spark, then chack all electrical connections to the coil, and then try swapping the no2 coil.

this should tell you where the problem is and it should just be a matter of changing the faulty part.
if this does not identify the fault please feel free to ask for further information

Removal & Installation

3.0L (VIN S) Engine

1. Disconnect the negative battery cable.
2. Unplug the engine control sensor wiring connectors from the ignition coil and the radio ignition interference capacitor.
3. Tag and disconnect the spark plug wires from the coil by squeezing the locking tabs, then twist the tab and pull upwards.
4. Unfasten the four ignition coil retainers and remove the coil and the coil ground wire the radio ignition interference capacitor. Save the capacitor and coil ground wire for re-installation of the coil assembly.
5. Wipe the coil towers with a clean cloth dampened with soap and water. Remove any soap film and dry with compressed air. Inspect the coil for cracks, carbon tracking, dirt or damage and replace as necessary.
   
   

   Fig. Ignition coil assembly mounting-3.0L DOHC engines
   

To install:

1. Place the coil, capacitor and the coil ground wire onto its mounting location on the right hand valve cover.
2. Install the coil assembly retainers and tighten to 45-61 inch lbs. (5-7 Nm)..
3. Apply dielectric compound D7AZ-19A331-A or its equivalent to the spark plug wire boots.
4. Attach the spark plug wires to their proper terminals on the coil and make sure the boots are firmly seated so that the locking tabs engage.
5. Attach the engine control wiring connectors to the ignition coil and the radio ignition interference capacitor.
6. Connect the negative battery cable, start the vehicle and check for proper operation.

Insert each wire on the proper terminal of the ignition coil. Ensure that the coil boots are fully seated and both locking tabs are engaged. The terminals are identified on the ignition coils. Install wires as shown in the illustration. The 2.3L firing order is 1-3-4-2 for both ignition coil assemblies.

Distributorless Ignition System In the distributorless ignition system (DIS), all engine timing and spark distribution is handled electronically with no moving parts. This system has fewer parts that require replacement and provides a more accurately timed spark. During basic operation, the EEC-IV determines the ignition timing required by the engine and a DIS module determines which ignition coil to fire.

Components
The distributorless ignition system (DIS) for the 2.3L twin spark plug engine consists of the following components:

• Crankshaft timing sensor
• DIS module
• Two ignition coil packs
• Spark angle portion of EEC-IV

Crankshaft Timing Sensor
The crankshaft timing sensor is a dual hall effect magnetic switch, which is actuated by the dual vane cup on the crankshaft pulley hub assembly. This sensor generates two separate signals, PIP (profile ignition pick-up) and CID (cylinder identification). The PIP signal provides base timing and RPM information, while the CID signal is used to synchronize the ignition coils. Initial timing (base timing) is set at 10 degrees BTDC and is not adjustable. Ignition Coil Packs
Two ignition coil packs are used for the 2.3L dual plug engine. The two ignition coil packs are triggered by the DIS module and are timed by the EEC-IV. Each coil pack contains two separate ignition coils for a total of four ignition coils. Each ignition coil fires two spark plugs simultaneously, one spark plug on the compression stroke and one on the exhaust stroke. The spark plug fired on the exhaust stroke uses very little of the ignition coils, stored energy, and the majority of the ignition coils, energy is used by the spark plug on the compression stroke. Since these two spark plugs are connected in series, the firing voltage of one spark plug will be negative with respect to ground, while the other will be positive with respect to ground. Refer to thePowertrain Control/Emissions Diagnosis Manual for additional information on spark plug polarity. DIS Module
The main function of the DIS module is to switch between ignition coils and trigger the coils to spark. The DIS ignition module receives the PIP and CID signals from the crankshaft timing sensor, and the SPOUT (spark out) signal from the EEC-IV module. During normal operation, PIP is passed on to the EEC-IV module and provides base timing and RPM information. The CID signal provides the DIS ignition module with the information required to switch between the coils for cylinders 1 and 4 and the coils for cylinders 2 and 3. The SPOUT signal (from the EEC-IV) contains the optimum spark timing and dwell time information. The dwell time is controlled or varied by varying the duty cycle (duration) of the SPOUT signal. This feature is called CCD (computer controlled dwell). Therefore, with the proper inputs of PIP, CID and SPOUT the DIS ignition module turns the ignition coils on and off in the proper sequence for spark control. CID is also sent to the EEC-IV micro-processor to allow for Bank to Bank fuel control. Failure Mode Effects Management
During some DIS system faults, the Failure Mode Effects Management (FMEM) portion of the DIS ignition module will maintain vehicle operation. If the DIS ignition module does not receive the SPOUT input, it will automatically turn the ignition coils on and off using the PIP signal. However, this will result in fixed spark timing (ten degrees BTDC) and a fixed dwell time (no CCD). If the DIS ignition module does not receive the CID input during engine cranking, random coil synchronization will be attempted by the module. Therefore, several start attempts (cycling the ignition from OFF to START) may be required to start the engine. If the DIS module loses CID input while engine is running, the module will remember the proper firing sequence and continue to fire to maintain engine operation. Dual Plug Inhibit
Dual Plug Inhibit (DPI) is a function of the EEC-IV that is only used when the vehicle is being started at temperatures -7° C (20° F) and below. During engine cranking, the EEC-IV will only fire the spark plugs on the right hand side of the engine. When the engine has started, the EEC-IV will send a signal to the DIS module to start normal dual plug operation. Ignition Diagnostic Monitor
The Ignition Diagnostic Monitor (IDM) is a function of the DIS module. The DIS module sends information on system failures to the EEC-IV which stores the information for diagnostic self test. The IDM signal also is used to drive the vehicle instrument tachometer, and test tachometer for system

Toyota Camry 1983-1996 Repair Guide Ignition Module - REMOVAL & INSTALLATION

External
All engines, except the 2S-ELC, have an external igniter.

1. Turn the ignition key to the OFF position. Disconnect the negative battery cable.
2. Separate the wiring harness connections.
3. Unbolt the igniter.
4. Loosen the nut holding the wire lead onto the coil.
5. Tag and disconnect the wire lead.
6. Lift the igniter off its mount.

To install:

1. Mount the igniter to the bracket.
2. Attach the wire lead to the coil.
3. Connect the harness.
4. Connect the negative battery cable. Reset any digital equipment such as radio memory and the clock if necessary.

Internal
REMOVING IGNITER WITH DISTRIBUTOR
See Figure 1
The internal igniter is only applicable to 2S-ELC engine Camry models. All other engines are equipped with an external igniter assembly.
Review the complete service procedure before this repair. Note position, color of wire and routing of all internal distributor assembly wiring.

1. Disconnect the cable from the negative battery terminal.
2. Remove the number one spark plug. Place a finger over the spark plug hole and rotate the crankshaft clockwise to top dead center. When there is pressure felt on the finger at the spark plug hole, this will be top dead center of the compression stroke on number one cylinder. If not, repeat the procedure. Install the number one spark plug.
3. Mark the position of the distributor flange in relation to the camshaft housing. Remove the IIA distributor assembly.
4. Remove the distributor cap with the wires attached, and remove the packing. Mark the position of the rotor relative to the housing and pull the rotor straight up and off the shaft. The distributor cap is held to the housing with three retaining screws.
5. Remove the ignition coil dust cover.
6. Remove the two nuts and spring washers and disconnect the four wires from the terminals on the side of the ignition coil. The wires are color coded yellow, blue, brown and red.
7. Remove the four retaining screws and remove the ignition coil and packing.
8. Remove the nuts and disconnect the pink, white and black wires from the igniter terminals. Remove the two igniter retaining screws and remove the igniter.

To install:

1. Attach the new igniter with the two retaining screws. Connect the pink, black and white wires to their respective terminals and install the nuts. Make sure that the pick-up coil wires are secured in their clips and that there is slack in the wires.
2. Install the ignition coil and attach it with the four retaining screws.
3. Connect the four ignition coil wires to their respective terminals and install the two nuts and spring washers.
4. Install the coil dust cover and push the rotor onto the shaft.
5. Place the distributor cap and wires into position. Install and tighten the retaining screws.
6. Install the distributor assembly and connect the negative battery cable.
7. Connect a tachometer and timing light to the engine and adjust the ignition timing.
   

Fig. 1: Make sure you remember where the colored wires attach for installation-2S-ELC engine

1. Reset any digital equipment such as radio memory and the clock if necessary.

REMOVING IGNITER WITHOUT REMOVING DISTRIBUTOR

1. Remove the distributor cap, rotor and di-electric insulator covers. Disconnect the red and yellow wires from the coil and the pink, white and black wires from the igniter.
2. Remove the igniter. It may be necessary to mark and rotate the distributor to gain access to the igniter retaining screws. The timing should be checked after the distributor is returned to the mark.

To install:

1. Install the new igniter using the two new retaining screws.
2. Twist the pick-up coil wires together, install the white wire first then pink and black wires to their original locations. Make sure the wires do not touch the housing generator or advance plate.
3. Route the red and yellow wires from the igniter so they do not contact moving parts. Connect the red wire to the right coil terminal (with the brown wire) and the yellow wire to the left terminal (with the blue wire). Replace the covers, rotor and cap.
4. Connect a tachometer and timing light to the engine and adjust the ignition timing.

Hope this helped (remember comment and rated this).

some tachs can take the signal from one of the spark plug wires; you just thread the wire into the bood with the plug, or into the other end of the spark plug wire.

2003 Chevrolet Malibu 3.1L SFI OHV 6cyl
Spark Plug Wires - Removal & Installation

3.5L Engine

1. Before servicing the vehicle, refer to the Precautions Section.
   NOTE Twist the spark plug boot one-half turn in order to release the boot. Pull on the spark plug boot only. Do not pull on the spark plug wire or the wire could be damaged.
2. Remove the intake manifold cover, if required.
3. Disconnect the left side spark plug wires from the spark plugs.
4. Disconnect the left side spark plug wires from the ignition coil.
5. Remove the spark plug wire clips from the Manifold Absolute Pressure (MAP) sensor bracket and the heater inlet and outlet pipe tab.
6. Remove the spark plug wire assembly.
7. If replacing only one plug wire, open the retaining clips and remove the appropriate spark plug wire.
8. Disconnect the right side spark plug wires from the spark plugs.
9. Disconnect the right side spark plugs from the ignition coils.
10. Remove the spark plug wire assembly.
11. If replacing only one plug wire, open the retaining clip and remove the appropriate spark plug wire.

To install:

1. Install the spark plug wire assembly.
2. Connect the right side spark plugs to the ignition coils.
3. Connect the right side spark plug wires to the spark plugs.
4. If replacing only one plug wire, open the retaining clip and install the appropriate spark plug wire.
5. Install the spark plug wire assembly.
6. Connect the left side spark plug wires to the spark plugs.
7. Connect the left side spark plug wires to the ignition coil.
8. Install the spark plug wire clips to the MAP sensor bracket and the heater inlet and outlet pipe tab.
9. If replacing only one plug wire, open the retaining clips and install the appropriate spark plug wire.
10. Install the intake manifold cover, if required.

Fig. 2.2L Engine Firing Order: 1-3-4-2 Distributorless ignition system



Fig. 3.1L Engine Firing order: 1-2-3-4-5-6 Distributorless ignition system



Fig. 3.5L Engine Firing order: 1-2-3-4-5-6 Distributorless ignition system



Fig. 2.4L Engine Firing order: 1-3-4-2 Distributorless ignition system



Fig. 3.1L Engine Firing order: 1-2-3-4-5-6 Distributorless ignition system



Fig. 2.2L Engine Firing Order: 1-3-4-2 Distributorless ignition system


Fig. 3.5L & 3.9L Engines Firing order: 1-2-3-4-5-6 Distributorless ignition system


I really hope help you with this (remember rated this help) Good luck.

possible ignition coil itself because tachometer takes signal from ignition coil.you may also have check engine light on too.

1. Note: Electronic Ignition engine timing is entirely controlled by the PCM. Electronic Ignition engine timing is NOT adjustable. Do not attempt to check base timing. You will receive false readings.
   

The CKP sensor is used to indicate crankshaft position and speed by sensing a missing tooth on a pulse wheel mounted to the crankshaft. The CMP sensor is used by the COP Integrated EI System to identify top dead center of compression of cylinder 1 to synchronize the firing of the individual coils.

1. The PCM uses the CKP signal to calculate a spark target and then fires the coil pack(s) to that target shown in Figure 51. The PCM uses the CMP sensor not shown in Figure 51 on COP Integrated EI Systems to identify top dead center of compression of cylinder 1 to synchronize the firing of the individual coils.

1. The coils and coil packs receive their signal from the PCM to fire at a calculated spark target. Each coil within the pack fires two spark plugs at the same time. The plugs are paired so that as one fires during the compression stroke the other fires during the exhaust stroke. The next time the coil is fired the situation is reversed. The COP system fires only one spark plug per coil and only on the compression stroke.
   
   The PCM acts as an electronic switch to ground in the coil primary circuit. When the switch is closed, battery positive voltage (B+) applied to the coil primary circuit builds a magnetic field around the primary coil. When the switch opens, the power is interrupted and the primary field collapses inducing the high voltage in the secondary coil windings and the spark plug is fired. A kickback voltage spike occurs when the primary field collapses. The PCM uses this voltage spike to generate an Ignition Diagnostic Monitor (IDM) signal. IDM communicates information by pulsewidth modulation in the PCM.

1. The PCM processes the CKP signal and uses it to drive the tachometer as the Clean Tach Out (CTO) signal.
   

2.5L V6

The ignition system consists of an ignition coil, spark plug wires and spark plugs.
The crankshaft position sensor signal is the basis for ignition timing calculations. The alternating voltage signal from the crankshaft position sensor is digitized by a pulse former within the powertrain control module. This digitized signal is then used to position the closing time of the primary circuit of the ignition coil.
Ignition timing is determined by the powertrain control module in response to engine operating conditions based on stored data tables or maps. Once ignition timing has been determined, the powertrain control module interrupts the current to the primary circuit of the ignition coil thus triggering the ignition spark which is supplied to the cylinders through the spark plug wires and spark plugs.
The ignition coils are triggered by the powertrain control module in pairs (cylinders 1 and 5, cylinders 4 and 3 and cylinders 2 and 6) sending one ignition spark to the firing cylinder and one ignition spark to the corresponding cylinder on the exhaust stroke. This ensures that any unburnt fuel residues remaining in the cylinder on the exhaust stroke are re - ignited to provide cleaner exhaust emissions.
---------------------------------------------------------------
2.0L 4 cynder

The ignition system consists of an ignition coil, spark plug wires and spark plugs.
The crankshaft position sensor signal is the basis for ignition timing calculations. The alternating voltage signal from the crankshaft position sensor is digitized by the powertrain control module. This digitized signal is then used to position the closing time of the primary circuit of the ignition coil.
Ignition angle is determined by the powertrain control module in response to engine operating conditions. Once ignition angle has been determined, the powertrain control module interrupts the current to the primary circuit of the ignition coil thus triggering the ignition spark which is supplied to the cylinders through the spark plug wires and spark plugs.
The ignition coils are triggered by the powertrain control module in pairs (cylinders 1 and 4 and cylinders 3 and 2) sending one ignition spark to the firing cylinder and one ignition spark to the corresponding cylinder on the exhaust stroke. This make sures that any unburnt fuel residues remaining in the cylinder on the exhaust stroke are re - ignited to provide cleaner exhaust emissions.
------------------------------------------------------------------------------------
Integrated Electronic Ignition System The Integrated Electronic Ignition (EI) System consists of a crankshaft position (CKP) sensor, coil pack(s), connecting wiring, and PCM. The Coil On Plug (COP) Integrated EI System uses a separate coil for each spark plug and each coil is mounted directly onto the plug. The COP Integrated EI System eliminates the need for spark plug wires but does require input from the camshaft position (CMP) sensor.
----------------------------------------------------------------------------------------