Hi!

I have a Civic 93 1.5 (D15b7) sedan that never gave me any problems until 2016 when it started the following problem:

When I turn the key on, the Check Engine light is on. The normal is to turn off after 2 sec. When you turn the key, you can't hear the click of the relay or the fuel pump working.

Then I leave the key turned on, after about 30 seconds to 90 seconds, you hear the click of the relay and the pump working. So the light turn off and I crank and immediatellythe car starts fine without any problem.

Once it get it work, the more I drive, the less it happens this problem. Example: when I leave home, it takes 1 minute to turn the light off, but if I stop at gas station, I turn the key on and the check engine light will turn off normal (2 seconds).

Replaced: brand new fuel pump, BN main relay relay, BN filters, BN TDC / CRK / CYL sensors, used ECU.

Gets the same symptom.

I've checked grounds, connectors, all fine. The car never got water inside.

I made the jumper and did not retrieve any code

WHILE CHECK ENGINE IS ON, CAR CRANKS BUT WON'T START

Does anyone have any idea what is this?

regards from Rio

 

You're going to have to test it while the problem is occurring. If you know exactly when the problem replicates itself, get ready to test it then and there. I would start by first checking to see if you're receiving power to your main relay.

I don't know your exact problem, but if I were to guess, I'd say it were either a bad ignition switch or a bad ECU, but you'll need to test both of those items when the problem is occurring.

 

I've tested three ECU and resulted same symptom. Ignition switch I checked and seems ok. When the weather is cold, delay more than 1:30 minute to hear relay clicking. This time is less than 30 seconds when the weather is hot. When car get wet, this time exceed 30 minutes
Before someone suggest water inside the car, this car is very clean inside, never get water inside, when drive in rain, stay dry inside. Smells like brand new, 41.000 miles

I suspect ignition module or tw sensor are bad.

 

How did you check it?

 

Honestly I don't know. A friend tested it and told me it's okay. How do I test the ignition switch on my own?

I've seen some people on honda civic forums with the same issue reported and they solved this issue simply exchanging or repairing the ECU.
I replaced an used ECU and there is the same symptom.
I'm so sad 'cause nobody knows how to start this troubleshoot. I've spent very lot of money replacing fuel pump, filters, sensors of distributor and so on.

 

sorry... exchanging = replacing.
danm auto-text

 

No worries, if you look in the FSM there's a procedure for testing the ignition switch, basically it just tests for continuity at different points with the key in certain positions.

Honestly though from your descriptions it sounds like a bad solder joint/connection somewhere because it's temp related. Finding that spot though might be tough. Like "slomofo" stated you'll need to test it on the spot when it won't start.

 

Already tested when occured. By the way, this happens always when the car is cold, so is easy to check when problem is in it. All power and ground ok. Procedures (voltage, continuity) involving wires of main relay to ecu, fuel pump to main relay and main relay to G101 results normal.

All grounds are tight and clean.

When I drive towards hot cities this never happens. When I drive to cold regions, this happens and get worse with rain.

My problem is between key OFF and key ON position. After 1, 2 or 3 minutes, fuel pump and relay click, I can crank and engine starts. Civic runs fine without any problem or symptom. You can drive miles and miles without any problem. :-(

 

Hi guys, I'm back. I brought my ECU from repair and I conected it to harness. Now, the fuel pump primes normal and engine starts.
If I could give you a council: trust in the blinks of the check engine light and never spend money changing parts by deducting possibles fails.

 

So what exactly did they repair?

 

They told me they replaced electrolytic capacitors and general review on the board.

 

Did they elaborate on which ones specifically? And how much did it cost you?

 

He didnt told me specific parts inside ecu.
Cost: $160.00 dollars

 

Hi brother I am getting the same problem with my 1994 sedan. So it means if my ecu is a little bit warm so there will be no problem. Like if I can get anyhow to make it thermally stable so it will not cause me any problem.
​​just getting the idea.
thanks alot

 

Hi. Replace your ECU or fix it