I walked out of work this morning & got in my car and began to start it. It was turning over but not catching. I checked the plugs, the battery connections and all wires. I had it towed to a local repair shop & they say it has spark, it is firing and has compression but they still have not been able to get it started. Any ideas?

If the Check Engine Light comes on for 2 seconds and then goes out, when the ignition switch is turned to ON (Position II), then focus on the distributor. Usually, replacing the Ignition Control Module (ICM) and coil, located inside the distributor, solves the problem. Be sure to apply silicone heat transfer compound to the back of the new ICM. This is an excellent time to replace the rotor and distributor cap, if they have not been changed in 60,000 miles.

Would you still be getting fire to spark plug if it was that?

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Originally Posted by TxGreaseMonkey

If the Check Engine Light comes on for 2 seconds and then goes out, when the ignition switch is turned to ON (Position II), then focus on the distributor. Usually, replacing the Ignition Control Module (ICM) and coil, located inside the distributor, solves the problem. Be sure to apply silicone heat transfer compound to the back of the new ICM. This is an excellent time to replace the rotor and distributor cap, if they have not been changed in 60,000 miles.

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Would I still get fire to spark plug if it was this TXGreaseMonkey?

In many cases, yes. A failing ICM can spark, but not when it is supposed to. I see this often on this site and it appears counter-intuitive. People think that their ignition system is not the problem, as long as it sparks. I recommend replacing these problematic components every 120,000 miles or 10 years, whichever comes first. Just make sure the CEL comes on for 2 seconds and then goes out, when the ignition switch is turned to Position II. It goes without saying that the under hood and under dash fuses should be checked with a test light or multimeter.

If the problem persists, after replacing the ICM and coil, focus on the Crankshaft Position Sensor.

Ignition Control Module (ICM or Igniter) and Coil Replacement

Bench testing ICMs and coils is virtually useless. It does not come close to simulating the extreme heat that often causes these components to fail. I recommend replacing these critical and problematic components every 120,000 miles or 10 years, whichever comes first.


1. Disconnect negative battery cable, recording any radio codes first.

2. Remove hex-head machine screws (3), securing distributor cap to housing, using an 8mm nut driver.

3. Move distributor cap and wires off to the side.

4. Remove machine screw securing rotor to shaft, using a precision #2 Phillips head screwdriver. A 1/4-inch drive magnetic bit holder (e.g. Wiha 52650) with a #2 Phillips head bit works really well. It may be necessary to "hit" the starter once or twice, in order to rotate rotor for access to mounting screw.

5. Remove rotor and leak cover.

6. Unfasten ICM wires, remove coil mounting screws (on distributors with a coil inside), and set coil aside. Trick: Removing the coil first, on distributors with a coil inside, improves access to the ICM.

7. Remove both screws securing heat sink to housing, using a precision #2 Phillips head screwdriver.

8. Remove heat sink from distributor and unfasten both screws mounting ICM to heat sink, using a precision #2 Phillips head screwdriver.

9. Clean connections with #240 abrasive cloth or steel wool.

10. Coat the back of the new ICM (or old ICM, if reusing) with a thin, even coat of silicone heat transfer compound. This special silicone grease increases heat transfer to the heat sink. Failure to apply silicone heat transfer compound will cause the ICM to quickly fail. Arctic Silver 5 is recommended by an AMHD member, which is available at Radio Shack.

If the ICM and the heat sink are simply placed together, the small air gaps (insulator) that naturally exist between them will inhibit heat transfer. By filling these gaps, the compound allows a direct path through which heat can travel. Failure to apply this grease is one reason why some Hondas suddenly die. Attention to detail makes a big difference with modern day electronics.

11. Mount ICM to heat sink and reinstall ICM, ICM terminal wires, coil, coil wires, leak cover, rotor, and distributor cap. Ensure female ICM connectors fit snugly--crimp with pliers, if necessary.


Conceptually, the ICM is a large output transistor (switch) controlling current through the primary coil. ICMs replace points and condenser in older vehicles. In the primary coil, current builds to 5 to 12 amps, generating lots of heat (due to inductance). Then, the trigger signal from the Crankshaft Position Sensor controls when the ICM "switches off" current to the ground wire of the primary coil, causing amperage to go to zero. When this happens, 12 to 14 volts in the primary coil is "stepped-up" to 30,000 volts in the secondary coil. This process creates a "type" of alternating current required for the coil (step-up transformer) to work. In a properly working ICM, timing is precisely when needed to fire each spark plug.

Bottom Line: ICMs and coils take a beating. If you don't proactively replace these components, you place your life on the line if they fail in traffic.

Note: Distributor cap contacts can oxidize or corrode, creating high secondary resistance, which can result in rotor and ICM failure, reduced mileage, CEL coming on, catalytic converter failure, or failed emissions test. The secondary ignition system will destroy the ICM and coil, if you do not properly maintain the ignition system. This means replacing the distributor cap, rotor, and spark plug wires every 60,000 miles.

WARNING: Intermittent ICM failure can allow fuel to build-up in the exhaust system. Detonation can then blow the exhaust system off the vehicle.