I have a 1991grand am it missing on the number 1&4 i have change the distributor cover sparks plugs both coils ignition module. had the compression tested it good at a shop by a mechanic they can't find what wrong. so does any body know what doing that.

The first step is to determine if it's a spark, fuel, or compression problem. Here's a quick way to find out which of the three is missing. Remove a plug wire, insert a Phillips screwdriver or spare plug piece of bare wire into the plug wire boot and place the end near the engine block (do not hold the plug wire while cranking the engine unless you want a shocking experience). If there's a spark when the engine is cranked, it has ignition. The problem is either fuel or compression. If the engine has an overhead cam with a timing belt, loosen the cover over the timing belt and check the belt. If the belt is okay, the problem is no fuel. Listen for the electric fuel pump in the fuel tank to make a buzzing noise when the ignition is turned on (you may have to open the gas cap to hear it). You won't hear anything if the pump has died. Diagnostics can now be focused on the fuel pump circuit to determine if the pump, relay or wiring is causing the no start. If the relay has voltage but the pump isn't running, you'll probably have to drop the fuel tank to check the wiring connector at the pump. If the problem is no spark, anything in the ignition circuit that creates the spark may be at fault. Use your AutoTap Express DIY to look for an RPM signal from the Crankshaft Position sensor while cranking the engine. A bad Crankshaft Position sensor is a common cause of no starts. The signal from this sensor goes to the PCM or ignition module that switches the ignition coil(s) on and off. If you have an RPM signal, a bad ignition module or PCM may not be switching the coil(s) on and off. Using a voltmeter, check for voltage at the coils with the key on and while cranking the engine. The voltage should be switching on and off. In ignition systems with a single coil and distributor, a bad coil or a cracked distributor cap or rotor can prevent the spark plugs from firing. On multi-coil, distributorless ignition systems and coil-on-plug systems; one coil failure may cause an engine to misfire, but it won't prevent it from starting. What's causing the no-start? All engines require three things to start and run: spark, fuel and compression. If any one of these isn't there, you aren't going anywhere

this generation of gm vehicles is easy to troubleshoot. the engine needs 3 things to run: compression, fuel, and spark. since you mention fire, i assume you have no spark.

disconnect any random spark plug wire and connect the end to a hei spark tester. crank engine and observe for spark. if you have no spark, disconnect the center terminal of the distributor cap and use the hei tester in the same manner. spark means cap and rotor bad or bad plug wireset. no spark means make more checks.

check for battery voltage and good ground on distributor. check for open or shorted ignition module or ignition coil windings. if power and ground is present and ignition coil tests ok, check for ignition pulses at coil primary. if you have no ignition pulses feeding the coil, change the distributor.

with that generation of vehicle, the ignition system will operate without help from the computer. don't even troubleshoot the guts of the distributor, if you change the cap, rotor, and anything else, it will be the same price as a remanufactured distributor, and might not fix the problem. if you troubleshoot a low volrage related issue (no pulses, shorted or open circuit, unstable timing, etc), change the whole thing.

Locate the ignition coils - they are mounted on the ignition module. Remove the wide connector that goes to the module. You will have to unscrew it first. Spray some WD40 on the connector pins and try to scrub them with a tip of a small screwdriver. Be delicate not to brake or bend anything. Reconnect the connector. Start the engine and see if it still misses.
If it still does, try to touch/move each of the wires that go to the ignition module. BE VERY CAREFUL not to touch any of the moving parts of the engine as you have to do it with engine running.

If it still misses, do the following.
1. Engine off
2. Mark the ignition wires so that you reconnect them later in the same order
3. Locate the coil which gives spark for cyl 1
4. Switch locations of this coil with any of the two remaining coils
5. Reconnect the wires
6. Start the engine

If it now misses on another cylinder, you will have to buy a new coil.

Missing problem requires to check the following systems and components:
1. Fuel system. (Fuel pump, fuel filter, fuel injectors).
2. Ignition system. (Spark plugs, spark plug cords or wires, ignition coil, distributor (cars with distributor type ignition system, rotor, distributor cap, ignition amplifier), Coils On Plugs (COP) and correct sequence of the spark plug wires and or Igniter connectors.
3. Air leakage in the intake manifold.
4. Detached vacuum hose.
5. PCV Valve.
6. Servo brake booster pipe or diaphragm.
7. Valve clearance.
8. Cylinder compression.
9. Contaminated fuel.
10 . ECM.

Hi, I believe there is a computer problem. If possible check codes for no start condition. if you know the no.#1 cylinder at TDC (Top Dead Center) on engine then you will know no#1 distributor is. Good luck.

Have a look at the ignition module. Cars of that vintage had a pretty basic electronic ignition system with an exterior module that worked in conjunction with the distributor. The ignition contacts on the key switch could be a problem and also the distribution of the spark plug leads. The firing order is 1 3 4 2 . Also check that you are firing on # 1 TDC compression and not # 4.

Have you checked the spark plug itself? --- 5.7L Engine To Remove:
NOTE: Note spark plug cable original positions before removing.

1. Before servicing the vehicle, refer to the precautions at the beginning of this section.
2. Clean the area around the coil with compressed air.
3. Remove or disconnect the following:
   • Battery negative cable
   • Throttle body air intake tube and intake box (if necessary)
   • Coil electrical connector by moving slide lock and pressing on release lock
   • Secondary high-voltage cable from coil
   • Mounting bolts
   • Coil from cylinder head opening by twisting

To Install:

1. Clean area around spark plugs with compressed air.
2. Apply dielectric grease to inside of boots.
3. Install or connect the following:
• Ignition coil to cylinder head opening
• 2 mounting bolts
  1. Torque to: 106 inch lbs. (12 Nm)
• Coil electrical connector
• Cable to coil
• Throttle body air tube and intake box (if necessary)
• Battery negative cable

---
Distributorless Ignition System General Information This vehicle uses two different types of ignition systems. The 3.7L, 4.7L, and 5.7L engines do not use a conventional distributor. The 5.9L engine uses a conventional distributor. The ignition system is controlled by the Powertrain Control Module (PCM) on all engines. Procedures in this section are for the 3.7L, 4.7L, and 5.7L engines; please see the section on Distributor Ignition Systems for procedures for the 5.9L engine.
Distributorless ignition systems (EI) are used on many current engines. This system uses the waste spark method for distributing secondary voltage. In a waste spark system, an individual coil is used to fire one pair of engine cylinders simultaneously. These cylinders are known as companions, since each of their pistons is at TDC at the same time. On a typical V6 engine for example, cylinder 1 is at TDC compression while cylinder 4 is at TDC exhaust. This is also true of cylinders 2 and 5 as well as cylinder 3 and 6.
The cylinder on the compression stroke is known as the event cylinder, while the cylinder on the exhaust stroke is called the waste cylinder. Since secondary resistance is very low in the cylinder on the exhaust stroke, little voltage is required to fire the plug. For this reason, the majority of available voltage is consumed by the cylinder on the compression stroke.
One spark plug is attached to each end of the secondary coil winding via the spark plug wires. This series circuit arrangement causes one of the plugs to fire in a forward direction (center electrode to outer electrode), and the other spark plug to fire in a reverse direction (outer electrode to center electrode). The firing voltage requirements on the waste spark ignition are significantly greater than a traditional ignition system primarily because it takes 30% more energy to fire a plug reverse polarity. When a spark plug is fired backwards, it fires from the outer electrode to the center electrode. This is a high resistance path since the electrons do not flow as easily from a cold, dull surface such as the outer electrode to a hot, sharp surface like the center electrode.
Since the coil and plugs are arranged in a series circuit, a typical plug gap of .050" results in a total gap of .100" for the whole circuit that includes two spark plugs for the companion cylinders. The waste spark can overcome this added resistance by producing high secondary output voltages due to low resistance in the primary winding. Another reason higher secondary ignition voltage is required is cylinder pressure; specifically, the lack of it. Generally, event cylinders require 10 to 12-kV to initiate current flow across the spark plug gap, while only 2 - 3-kV is needed to fire the waste cylinder. Therefore, the air gap in the waste cylinder creates no more resistance than the rotor gap does in a conventional ignition system.
There are two different methods used for coil trigger. One method sends the crankshaft sensor signal directly to the ignition module to activate the coils, while the other sends the crankshaft sensor signal to the PCM and the PCM controls ignition operation either directly or through a separate ignition module.
Waste spark ignition advantages

• It has fewer components than conventional distributor-type ignition systems.
• No mechanical adjustments to set ignition timing.
• No mechanical load (turning the distributor shaft).
• No unwanted timing variations caused by gear lash or other worn distributor components.

Another advantage of waste spark is longer coil life. To illustrate this point, consider a six-cylinder engine with conventional ignition. At 3000 RPM, the coil must fire 9000 times per minute. This is calculated by dividing the engine speed by 2, since the cam turns at half crank speed, and then multiplying the distributor RPM by the total number of engine cylinders.
In contrast, the coils on a six-cylinder engine with waste spark only work a third as hard. This is because there's a coil for every two cylinders and each coil fires every crankshaft revolution. This means that at 3000 RPM, the coils only fire 3000 times per minute. This allows each coil to operate with less dwell (time that the coil is energized), resulting in less heat buildup and longer life.
Coil Over Plug System The coil over plug system was developed so that spark and spark timing could be better controlled on an individual cylinder basis. Each cylinder has an ignition coil mounted directly above the spark plug on the cylinder head cover. A short suppresser/connector replaces the spark plug wire and links the coil to the plug. There are different methods used for primary triggering. Some manufacturers use a combination coil/module, which means each coil has its own control circuit that is activated by the PCM. Others use remote mounted modules to trigger the coils.
Each individual coil is allowed to saturate while all other cylinders fire. For a V-8 engine, this allows a period of seven firing events for coil saturation, compared to three events for the same V-8 engine with a waste spark system. The coil over plug system also benefits from a minimum amount of energy lost, due to the resistance of spark plug wires.
Coil Near Plug System The coil near plug system also features multiple ignition coils. An ignition coil/module is mounted in proximity of each cylinder. There is a short length of spark plug wire between the coil and the spark plug.
Each ignition coil/module has its own control circuit and is activated sequentially by the PCM. All timing decisions are made by the PCM. This includes both ignition timing and duration of the spark.

Needs to check and make sure timing belt is not broken, if that checks good, more then likely it's going to be the ignition control module, sit in the distributor, also have him ohm ignition coil. but more then likely if timing belt is good, ignition module.

Try this...

You need to check for spark at the number 1 spark plug if no spark then it could be a few things
1.crank shaft position sensor
2. distributor cap or plugs
3. pick up coil inside distributor
4. ignition coil
5.ignition module
6.Blowen fuse check both engine fuses and inside cab fuses
7. oil pressure switch
You can pull the coil wire going into the distributor cap and check for spark there if no spark there then your problem will be from the ignition coil back

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).