I have a 1992 Honda Civic which I purchased from a friend about 6 months ago. The car has had no major issues in the past and has had all normal maintenance performed. About six weeks ago the car began to not start. The engine would turn over but it wouldn't start. I noticed the fuel pump wasn't priming. At the time, if I kept moving the key from the off to on position, eventually the fuel pump would prime. The issue got worst and then it wouldn't prime all together.

The car had a new distributor and main relay put in and then the car ran normal for about 2 days.

The car had a new fuel pump put in and it ran fine for about 2 days again.

The car had a new ECU put in and it ran fine for about a week.

Now it requires the car to sit in the ON position for about a half hour on average for the fuel pump to prime, that is when the car is cold. If I run trips and stop at a store, it may take a few minutes, which is obviously still too long.

I've checked the main relay and it's fine. I read somewhere online that the fuel cap could have a leak, so I replaced it. ECU and Backup fuses are fine, along with all the other fuses under the hood. Before the car primes, the Check Engine light is on but no code.

Does anyone have any ideas why this is happening? I don't know squat about cars so if you need me to check something, please be specific. Could this be something dumb like it needs a new fuel filter? I already read that the ECU may not be properly grounded but I'm not sure where is it grounded. I'm lost on this one!

. Clean the main ECM ground, located on the thermostat housing. Look for a 3-wire brass connector.

. Turning the ignition switch to ON (Position II), not START, does the CEL come on and then go off after 2 seconds? If not, the problem is with the ACG (ALT) (S) 15 amp fuse, in the under dash fuse/relay box; ECM (perform the K-Test, below); main relay; or the ignition switch. Perform tests in that order.

The K-Test: Remove the MAP Sensor connector and turn the ignition switch to ON (Position II). Using a multimeter, check for 5 volts going between the MAP Sensor connector's reference wire (+) and ground. As you look at the connector, this is the socket on the right. Really press the black test lead into a cleaned main ECM ground on the thermostat housing. If the voltage is low, it's probably indicating ECM failure. Most failed ECMs will record a fraction of a volt. To me, the K-Test is simple, elegant, and accurate. Many Hondas parked for several years are now back on the road. "The K-Test creates massive value, by providing a low cost solution where one did not previously exist."--TxGM

Let me know the results of the K-Test. I suspect the ECM is intermittently failing.

Fuses are fine, main relay is fine, never tested the ignition switch. Performed the K-Test and the reading was just under 3volts. Next question is, the original ECM went in it, and then a new ECM was placed in it and went as well, and than a 3rd. Why

Were ECMs #2 and #3 from salvage or off eBay? If so, fish in a different pond. The K-Test is showing ECM #3 is failing.

For ECM #4, shop for price and WARRANTY.

First one was the original one. Second was new but I returned and got my money back. Third was off eBay used. The 2nd and 3rd started to die within a few days of being installed. Seems odd.

I've never encountered this problem before. Are you properly grounding yourself, prior to handling the ECM? There may be a voltage spike coming from somewhere. This will take patience and a lot of testing.

Sorry, I tried the K-Test again and it came back fine. I also brought the car back to the garage who has been working on it and they tested the ECM and it is fine. Seems like issue doesn't happen after it sat in the garage overnight and...

They replaced the ignition switch and the issue didn't exist for two days and then started again. Mechanic was pushing on wires behind the fusebox in the car and the fuel pump kicked in and started. So he replaced fuse box and the car started...

Right up but of course the issue occurred again the next day. I suspect possibly a crack in the wire harnass or could the fuel pump be producing any issues here?

Even though not common, those issues are always possible. It takes patience and a multimeter, to solve most continuity problems.

Seems as if it's the ECM. I read a lot about ECMs delaying power to the fuel pump when cold out. So I took the ECM out and left it inside last night. Brought it outside this morning, hooked it up and started right up.

So it seems as if I need a new ECM... or a nice jacket for the ECM so it can stay warm in the winter LOL.

Never seen that problem before. I've seen these ECMs work at -35 degrees F in Alaska. Try spraying the connectors with WD-40.