90 Honda Civic Wont Start Bad ECM?

unless this car went for a swim, the ecm's are not a common problem.

nope no swimming! Thanks

When you turn the key to ON, does the Check Engine light come on for two seconds then go off? Do you hear the fuel pump operate while the light is on?

Is there power to the ignition feed wire that goes to the igniter?

Is the distributor rotor resistor blown?

Is the coil dead?

There are a great many very basic checks you need to do (and have not done) before condemning something like the ECU. I've been told by a very reliable source that Honda engine computers quite simply do not go bad unless subject to severe trauma of some sort.

I had a simular prob with a prelude.ended up the set screw came loose on the rotor...put screw back in and away we went.

I'll check about the engine light... Its got a new dist which has the coil built in. The fuel pump is working, I checked that. I was mainly curious if the ECU light should flash anything at all under normal circumstances. The haynes says it should flash when the computer is turned on, but I get nothing. I'm going to see if I'm getting a voltage pulse to the injectors tonight. If I'm getting power to them, then I know for sure the ECU is good! Maybe the new dist. is bad--I'll check it out after the injectors.

Thanks again!

Leave the damn ECM alone until you make sure that *nothing* else is at fault.

I had an acura integra that wouldn't start due to an ignition problem. Ohmed out the coil and it was fine. Replaced the ignitor and that didn't help. My next thought was to replace the output transistor on the ECM. Pulled the ECM out, took off it's cover and was struck by how it was the finest piece of electronics I'd ever witnessed. It put mil-spec assemblies to shame. I put the cover back on, reinstalled it and started looking elsewhere. Put an oscilloscope on it's output at the ignitor and discovered that it was putting out a pulse like it should. I then replaced the coil that had ohmed out perfectly and that fixed the ignition problem.

The distributor isn't really "new" is it? I'd wager it's actually an aftermarket rebuilt unit. Not the best thing for your car.

Then the ECU is fine. The ECU is what turns the pump on via the main relay. In fact, unless you have a multi-port injected Si, injector power AND fuel pump power come from the same wire out of the main relay in your car.

Your Civic has throttle-body injection, doesn't it? You said before you knew you had fuel delivery, but you had no spark.

If you can see fuel being sprayed into the throttle body, then checking the injector is irrelevant.

Perhaps you should check to see why you haven't got spark. I'd start with the igniter and the coil. Both are notoriously unreliable in "new" distributors that aren't actually "new".

Then your old coil was grounding through its body, something a VOM won't catch. Potted coils overheat quite readily, so you need to make certain HT current always has a proper place to go.

Isn't it amazing how many people want to replace the one thing they understand least? Maybe because they have no idea what's going on inside the ECU, and therefore it MUST be bad?