[angelmom2006]

I wonder if that is my cars problem. Last night my car just wouldn't start. 1992 honda civic dx/lx 1.5L 16 valve 4 cyl automatic trans. It cranks but doesn't start. My dad said the spark in the wires to the plugs isn't arcing like they should. Some less than others. Fuel comes out of the pump and my dummy lights turn off after 2 seconds with the key on. Just put new plugs and valve seals (cover gasket) on last week because I found oil in two of my plugs. But for two weeks now it tries to stall out at stop lights or would take awhile to start. Now it won't start. It's stuck at my kids school where it decided to go on vacation. What all could be the problem and how do I find out if it's the problem? Please ask if you need more info and I'll try my best!!

[TxGreaseMonkey]

Replacing the Ignition Control Module (ICM) and coil inside the distributor should solve the problem. Be sure to apply silicone heat transfer compound to the back of the new ICM. You really should replace the rotor and distributor cap, while you are at it.

[TxGreaseMonkey]

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 ECM controls when the ICM "switches off" current to 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.

[angelmom2006]

I will confer this with my dad as I think he was thinking the same but wasn't sure and I'll let you know how it turns out. Thank you!

[angelmom2006]

Can you check the coil? How could you do a coil check? What should the readings be?

[TxGreaseMonkey]

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.

This is really the way it is. These are popular cars for thieves to steal for parts--I would get it fixed and get it home.

[angelmom2006]

This is really the way it is. These are popular cars for thieves to steal for parts--I would get it fixed and get it home.

We towed it home on the car dolly yesterday. Replaced the coil, cap and rotor. Spark is great now but still doesn't start? What Next??

[TxGreaseMonkey]

Replace the Ignition Control Module (ICM). With a failing ICM, you can have spark but it doesn't fire precisely when the ECM (computer) directs; thus, you need to install a new ICM. It's important to verify that the Check Engine Light comes on for 2 seconds and then goes out, when the ignition switch is turned to ON (Position II).

[angelmom2006]

Replace the Ignition Control Module (ICM). With a failing ICM, you can have spark but it doesn't fire precisely when the ECM (computer) directs; thus, you need to install a new ICM. It's important to verify that the Check Engine Light comes on for 2 seconds and then goes out, when the ignition switch is turned to ON (Position II).

ICM is fine. Car started finally... I went to check the relay again( under the left side dash) but in trying to disconnect it I bumped into something that made stuff in the car go crazy. I called my dad out to do the same and it did it for him too. Upon further inspection it looks like an improperly disconnected after market alarm or something. My dad did something to it and now the car starts. He believes it was shorting out the relay connection for the pump and what not. Car starts every time. But the distributor and such did need replacing. It gets great spark now. Even in broad daylight you can see it!! Thanks for all your advice... It really did help and on these cars it's so cheap!!

[angelmom2006]

This is really the way it is. These are popular cars for thieves to steal for parts--I would get it fixed and get it home.

Coil was failing all the readings it should have.! You're a genius.

[TxGreaseMonkey]

Did you verify that the CEL consistently comes on for 2 seconds and then goes out, when the ignition switch is turned to ON? If not, the car can still let you down.

[angelmom2006]

Did you verify that the CEL consistently comes on for 2 seconds and then goes out, when the ignition switch is turned to ON? If not, the car can still let you down.

It's functioning normal. Lights and everything do just what they are supposed to. Car is very smooth now. Sounding great and running great. Ripped that alarm thing out today and all windows, locks, doors, lights etc are no problem.

[TxGreaseMonkey]

Good job!