civicali

1994 Honda Civic LX 1.5L

We've been having issues with starting a Civic.
Will not start when its raining or after a rain event.

During and after a rain event, check engine light stays on for a very long time (cannot hear the fuel pump priming) and doesn't turn off when turning the ignition (but not trying to start or crank car).
Car starts fine on warm days, with no rain. The check engine light turns on and off when turning ignition and the fuel pump buzzing sound is heard.

We have replaced the spark plugs wires, cap and rotor, fuel filter, and main relay.
All work was due anyway except for the main relay.
Replacing the above parts has not solved problem.

Do we have a problem with the ECM?

Is there a test that can be performed that will point to a bad ECM or a bad connection somewhere.
Again, issue is happening during and after a rain event.

Any advice is greatly appreciated.

tony_2018

Check your grounds, all of them, in the engine bay.

NVturbo

is there any water leak near the ECU?

civicali

Going to locate the ECM first and look for obvious water leaks

NVturbo

It's passenger kick panel, underneath the dash

Outrun

Same thing happens to me in rainy or humid weather. Takes 30 seconds to 21 minutes (longest wait I've experienced) before the fuel pump primes.

civicali

We removed the ECU/ECM and the repair shop discovered several bad capacitors.

Main relay also replaced.

We are still experiencing the same issue. When it rains or after a rain event, the car does not start, it only cranks. You can see the CEL illuminated throughout the cranking and does not go away. If you wait long enough, while only turning the ignition key to “on” position, the CEL will eventually turn off after a few minutes and is followed by the fuel pump prime. This is when you are able to turn the car on.

CEL should be turning on and off immediately after turning the key to the “on” or “start” position, but it’s nit happening when it rains.

Please advise

muellersfan

Did you replace or repair the ECU?

Purchase and install a known good ECU that comes with a guarantee.

civicali

We got the original repaired and we got a lifetime warranty on it. You never know, it just might be the ECM.

muellersfan

Get a refund or return ECU to shop so they can now replace the capacitor that is actually blown.

NVturbo

go to your nearby salvage yard and pick up a P06 ECU. Swap it out and if the problem goes away, bad original ECU.

muellersfan

It is.

tony_2018

Wasn't a good repair..they should've test it but than again its not easy to replicate a test environment in a shop.