albert7

Hello, does anyone have an update on this problem found in this thread? I drive a 1995 Honda Civic, and have the same problem! After it rains, my car won't start. I was told to turn on the ignition half way, wait for the dash lights to come on then to go off (3 seconds), and then start it. It worked perfectly the first few times, including this morning. It's currently the afternoon, and it's raining. This time, when I turn on the ignition half way, the lights come on but won't go off, so the car won't start. To backtrack a bit, when this problem happened before, my mechanic changed the fuel pump, so that's obviously not the problem. Can someone please help?

Btw, I know NOTHING about cars, but from my quick research on the Internet, it seems like the problem can be:

1. The ECU is bad and needs to be replaced
2. The distributor is fried and needs to be replaced
3. The main relay is bad

Please advise me what to do. Thank you so much in advance!

civic402lx

Check ground for corrosion. Especially the one from chassis to tranny. If its green and oxidated. Replace. Check battery terminals for corrosion. Clean if need be.

TomCat39

Moved your post and the reply to it's own thread as is customary and added a link to the old thread that is similar to your issue.

Thank you for providing complete car details and searching for information regarding your issue. The effort is appreciated.

I hope you find the help you need to correct your issue.

Of note, have you checked the rubber seal on your distributor cap? I recall another user not long ago reporting the same issue of problems after it rains and their problem turned out the rubber o-ring on the dizzy cap didn't sit right when they put it on and so there was a gap that allowed moisture in. I think their car was misfiring though so may not be your issue per say but it's easy to check to be sure.

Best of luck.

92civicdxx

by chance is your intake the type that the filter runs down almost to the ground? I've gotten water in the intake before and has this same problem it will spudder when trying to start

albert7

Okay, so here's an update. I waited another 20 minutes or so, then tried the trick of turning on the ignition and waiting for the check engine light to go off. I waited perhaps 1-2 minutes, and nothing happened. I somehow felt if the check engine light didn't go off in 2 minutes, there's no reason it'd go off in 3 or 5 or 10 minutes! But it did! I waited perhaps 2-3 minutes, and saw the light go off and the fuel pump prime! Afterwards, the car started with no problem!

Key takeaway: leave the ignition in the on position for 1-5 minutes, and the car should be able to start! I assume the problem has to do with the ECU, so it probably needs to be placed. However, rather than spending more money to get this fixed, I could just keep doing what I'm doing to get the car started, and it should work every time, correct? It won't damage the car, correct? Again, this problem of the car not starting only seems to happen when it rains anyways, and it seldomly rains here.

TomCat39

Pull the CEL codes, there is very likely codes stored if it took more than 2 seconds for the CEL to go off.

It may indicate a problem that is present that is not the ECU.

albert7

I know nothing about cars, as I only just recently researched what may be wrong with my car. What does it mean to pull the CEL codes? How do I do that? I've never worked on my car before, and was just going to take it to my mechanic.

TomCat39

You have a 95 civic so this is OBD1. There is not a universal scanner for you or most shops to use, even the Honda dealerships may not have the Honda exclusive scanner for these cars anymore. Instead you short the service connector and read the blink code from the dashboard. On year 96 and above vehicles they became semi standardized with OBD2 and there is a universal scanner anyone can "pull" codes from the ECU.

There is a sticky at the top of the forum expressly explaining how to pull your CEL codes.

https://honda-tech.com/forums/honda-...lists-1901557/

I have linked it above for you.

94 Civic Si

I would suspect other things before the ECU.

Grounds - are the connections at the battery terminals clean and free of corrosion? Body to tranny ground? G101 at the thermostat housing?
Main Relay - these go bad, and can function randomly. Did your mechanic want to replace this before replacing the fuel pump? I am guessing this would be a less expensive repair than replacing the fuel pump...

94 Civic Si

Ron J posted this in the previous thread - re-soldering the main relay - good stuff!

Main Relay Fix, Troubleshooting (Honda, Acura) and how to solder

weekendboost

Did you already check the main relay? I had water in mine once from rain.

delsolintegra

It's probably the capacitors in the ECU fuel pump priming circuit. When they get old they become a little bit porous and absorb moisture and short out. Leaving the ignition switch on for a little bit may run current thru them and dry them out just a little bit to complete the circuit. These ECUs are 20 years old ! Some people have luck changing out the capacitors (some kits are sold) but you have to have some soldering skills. I just bought a junkyard replacement ECU for about $125 and wrapped some plastic cloth around it when I installed it to keep moisture off it.

It is an intermittent problem until the caps totally fail. I often thought about drying out the ECU with a hair dryer and possibly coating the caps with some kind of sealant, nail polish or whatever but I never got that far.

testify

Check for moisture under the distributor cap. Even the smallest amount of moisture can cause this condition.

If you find any moisture, and maybe even if you do not, spray the cap and distributor with quick dry electonics cleaner to get rid of the moisture and seal it back up and the problem will be gone until it rains again.

The solution is to replace the entire distributor cap or just the gasket.

edit: nevermind. Check for a torrent of water flooding your ECU from a leaking windshield.

albert7

Hey everyone

Thanks for your help so far! It's been raining on an off here. When there's no rain or moisture, my car starts fine. When there is rain or moisture, I have to turn on the ignition and then wait from one to twenty minutes (until the dash lights go off), then start, and it works every time!

However, today we had some light mist/rain, and after waiting shortly for the dash lights to go off, I tried to start to the car but it won't even churn over! Does anyone know what could be wrong this time? If I wait until until there's no more moisture/mist, will my car churn over? Again, previously the car always churns over when starting it after the dash lights go off. Now it's not churning over at all.

I did buy a refurbished 1995 Honda Civic ECU online for about $200 (which my mechanic said to do) and he'll charge about $80 to install it. I haven't brought in my car to have it installed yet, but should this fix this problem of my car not being able to start when it rains?

Please chime in if you can. Thank you very much!

civic402lx

Wow $80 to pull the carpet over, unbolt 2 nuts, unplug couple of harness.
you don't want to try that yourself?
1. Unplug negative battery post, leave it off.
2. Locate ecu, below glove box, to the right kick panel
3. Pull carpet and trim to expose ecu
4. Unbolt nuts with 10mm socket and ratchet
5. Unplug ecu harnesses
6. Plug harnesses into NEW ecu

reverse all steps and you are done.

Simple really. Give it a try.

Save yourself $80

albert7

Here's a quick update. I called my mechanic and he said it may just be that my battery is running low! Hopefully that's the case, but I do believe I changed to a new battery just 2-3 years ago. If not the main battery, my coworker suggested it may be a bad main relay. I'm going to try and jump start the car tomorrow, so hopefully it starts and I can take it to my mechanic to get the battery replaced.

mk378

Haven't you already replaced or rebuilt the main relay? Having to wait for the CEL to go out before the car can be started is either the main relay (most likely) or the ECU (bad ECUs are not common but when you do have a bad one, it is likely to do what you are saying).

If the starter sounds like normal when you crank it, but the engine doesn't fire, it's not the battery.

albert7

civic402lx: I really know nothing about cars, have no idea what all the different technical terms are, and don't even have the tools to unbolts the nuts or whatnot. I wish I were more "handy," but that's just not me.


mk378: I don't believe I ever mentioned I had my main relay replaced or whatnot. My mechanic said the issues with the car not starting is likely due to an old and worn out ECU, so I bought a rebuilt one for $200. How much does it cost to replace the main relay on a 1995 honda civic?

***An update: my brother tried to start the car while I was gone, and he said it actually cranked, but did not start! It likely didn't start because the CEL was still on (just as with before). My question is if my brother was able to crank the car, that means the issue is NOT the battery, correct? Therefore, the likely issues with my car is likely due to a bad ECU, right?

crazyhorse2011

You don't need a mechanic to replace the battery.
You don't need a mechanic to replace the ECU.

Pro tip:

If you don't have on already,go buy a slow charger, can be had at most auto parts stores or walmart. Get one with a low amp rating, like 2.0A or 1.5A or something low. Dont get like 20A or 75A. Hook the battery charger up to your positive and negative battery terminals and leave it charging your car all night.

Next morning: unplug charger, remove from under hood. Open passenger door and peel back the carpet from under the glove box. You will see a gray box the size of a text book in there. That is your ECU. Use your 10mm wrench to undo the nuts holding it into the floor. Unplug the 2 cables from the box. Now take the ECU you ordered and reinstall. Plug harnesses into new ECU, put nuts back in place, put carpet back over it.

Now your battery is deep charged, and your ECU is replaced.

Get in the car and start it up and report back to us. If your battery is actually shot it will drain out again in the next few days or weeks, but a deep cycle charger should get it fully topped off for at least one good crank so we can actually see whats going on here.

And as previous posters said, check the ground wires, if you need pics of these ground wires just say so.

crazyhorse2011

If the car didn't start but was cranking, then the battery was fine.

However, we cant be certain that the ECU is the culprit just yet until you do what i posted just above this post.

mk378

The main relay is the same kind of replacement as the ECU, unbolt and unplug. It is a little harder to reach it is on the other side of the car above the handle that opens the hood.

When you have an older car it is good to be capable of doing many repairs DIY, hiring mechanics will get expensive.

dsol

Had this issue with my 92 civic... I suggest checking the carpet under the dash to see if its damp. on mine it turned out that the previous turd who owned it cut a hole in the cowl, so when it rained it leaked down onto my main relay and fuse box.
Also, take the 15 minutes to swap out the ECU your self. there is a few step-by-step lists these guys already posted that lay it out. its VERY easy. If you need visuals youtube has all the vids on this you could want. It might seem difficult if your not "handy" but even if you had trouble and it took you 30mins...you just saved $80.
On a side note, if your mechanic is charging $80 for a 15 min job, find a new mechanic. No need to have a mechanic who is charging $320 an hour for a 95 civic.
Hope you find your issue!

civic402lx

Click and watch.
battery replacement, on video.

albert7

Thank you for the help thus far! This morning even though it was raining, after waiting for the CEL to go off, I started the car, and it started without a hitch! So I'm ruling out that the batter was the problem (only replaced it 3 years ago). It's just awkward that yesterday it was also moist and cold, and my car wouldn't crank, yet this morning it did crank even with the rain!

The problem seems intermittent, so knowing nothing about cars and just using logic, I hope the problem is just the ECU! After reading your comments on how easy it is to remove the old one and replace it with a new one, I'm going to try to do it myself to save $80

I don't think I have the proper tools to unbolt the (10mm?) nuts like a socket and ratchet, but I could just just an adjustable wrench, correct? According to you guys, there'd be a total of 3 nuts to unbolt: the one nut for the negative battery post and the two nuts holding in the ECU, correct? I watched some videos on youtube about ECU replacement but their ECUs are slightly different than mine. There's 4 claws on the refurbished ECU I bought......what are those for?

crazyhorse2011

Go to home depot.
Buy ratchet
Buy 10mm socket

Even better just buy a set, you'll be able to do a lot of work with just a ratchet set.

And your battery issue sounds like a grounding issue. Check your ground wires. I can upload pics.