On the ECM. The reason I said the ECM is the least likely culprit is that I've seen so many people on this forum swap out the ECM... and no fix.

But the rain... let me tell you of my experience. About 10 years ago I left the sunroof open on the Rx7 (which I still have, and still runs perfectly, although I haven't listed it below). Well we had an unbelievable overnight rain that dumped 12" of rain.. and strong winds. It blew under the sunroof because of the wind. Left several inchs of water on the right passenger well. And of course the ECM was under that. I replaced it, used RTV to make it waterproof. Started right up, and has run perfectly ever since.

On the ohmmeter.. that last line... I think that is a typo. A fuse will test shorted if good, not open. Open means infinite resistance... which is what a blown fuse is. Short (not a bad thing when you are SUPPOSED to get zero ohms) means zero ohms.

Also, making good contact is an art form.. or rather a skill. Practice on some grounds on the vehicle.. Say ground at the center of the NEG battery post... to the engine. The leads are sharp because corrosion on many tests point keeps the lead from making proper contact.

On the test.. I understand it, or at least I could figure it out if the distributor were in front of me. For now... I think you found the problem... so find a cheap, good ECM is first order of business. Btw, I don't think the ECM has to be working to make those tests... not sure. But the instructions are clear.

If you had spark before you had this problem... I wouldn't bother with the checks. It is not likely that any of the components have gone bad just sitting.. or even if they were rained on. The pickup coils are "passive", just a coil that picks up a pulse as the distributor rotates... not a high voltage at that point.

 

Mine was/is in the black fuse box under the hood....further corner to the left as I'm standing over it. There's a nifty label under the lid that helps, too.

 

Believe it or not, I know exactly what you're saying...and had an idea of where you were going with it. This is like the O2 sensor...just because the light comes on for the sensor, many believe it's the culprit when if fact it's only responding as it should to an exhaust mix problem. So, I've learned a little about diagnosing.

On the RTV and ECM...
Interesting story. How did you apply the RTV. I'm going to do that on all of my vehicles.....damn it!

The ohm meter...
Oh....my bad. I thought infinite meant no continuity and open mean closed circuit.

On everything else...
Okay, I'll bother with the tests post new ECM if I have to. Saves me some time to do other things, anyway. The coil test still has me curious, though. And we see curiosity brings me....

Anyone have a good, used ECM? I'm in the market. (Next stop: the marketplace)

Thanks Richard!

 

RTV is the old term for Silicon Rubber. On mine, the box that contains the ECM is an aluminum box with slight spacing at the edges. Basically what I did was smear the sealant along the edges... using enough to make sure it was sealed, but as little as possible as I was worried about overheating. Turns out overheating is not a problem, while water and moisture certainly is.

 

Oh, I have plenty of "RTV"/silicone around....and my box is the same. So, that's a'what I'm a'gonna do. Thanks, again.

 

huh, thats not where mine is. There is one for the head lights in that black box, and one I put in there that replaced the efi main relay (it's probably now in the location your is in). Oh well, not really too concerned about it since I don't use it anyway. I actually don't even have the 15amp fuse in there anymore.

I did find the circuit opening relay, which is behind the front right speaker.

 

Something was causing that fuse to blow... you might consider adding a 20 amp inline fuse just to protect your ECM. Cheap and easy to add.

 

You might also consider possible long term electrical effects of not running the vehicle with a relay.

What it does...in case you didn't know:
http://www.tegger.com/hondafaq/mainr...ion/index.html

 

Mathew... you are right.

 

Sometimes....

 

I put a relay in where your efi main relay is (theres an open spot for it in my rig). Figured it'd be a bad idea to leave the fuel pump on 24/7. After the relay I have a fuse for the fuel pump and another fuse for the ecm. That way if the fuse blows again I'll know if it's the fuel pump or ecm.

 

What motor do you have? If it's the 3vze, I know there are differences from year to year. I suppose the EFI relay location is one of them.

The original locations for EFI fuse is before the relay...to protect the relay as well as the components beyond it. But, I suppose as long as there is a fuse (15amp?) before the pump and ECM you're protected. Just not the relay itself. I am curious, though, where is the original location for your relay? You never said. That blank spot where you put yours may not be doing anything for the ECM, etc.....I don't know. I guess I'd have to know more about your year of vehicle....how it's wired.

 

I have an 89 3.0 4runner, suppose I should put that in my sig. I never did find my efi main relay. Don't realy care at this point (I am curious though), but I have a feeling it's somewhere hidden up in the dash. The place I have mine now there was nothing there except a hole, it's just kinda sittin in there now. I thought about putting the fuse before the relay, but if it does blow again I need to know what's causing it. I can always steal another relay from something else if I had to. The head light relay would be easy to use, it's sittin right next to my new EFi main relay. theres also one in the dash for A/C or heat that i saw when tearing the dash apart.

 

Here is another way of testing fuses. Put your DMM to DC volts. If you get voltage readings on both sides of the fuse, it is good. If you get voltage on one side of the fuse, you have found the supply side (or where the voltage comes from) and no volts on the other side means the fuse is blown, replace it.

 

If you have a DMM with a diode function it will beep when there is a dead short, or zero ohms, Beeps are good when checking fuses and wires.

 

Or you could just look at the fuse.

 

Oh, you just take all the fun out of it...don't you?

Phildelfino....there's one thing, though. If voltage is getting through a fuse (provided the fuse is good) 12v will show on both sides....making it impossible to determine the supply side unless you visually determine that or the fuse is blown and voltage only gets to the supply side.(EDIT: I just realized after rereading three times that is what you saying...yes?)

The diode function is cool, though. You don't have to pull the fuses saving wear and possible breakage on the connections, and those suckers are actually sometimes hard to pull out....PITA. Especially in tight spots like behind the kickpanel under the dash. I can test all the fuses in half the time with a meter rather than pulling them all out one by one. Beep...beep....beep....beep.... (I think I'm becoming a gadget nerd)

 

Does the fuse box under your hood not look like this in the picture to the bottom left?
http://www.4crawler.com/4x4/CheapTri...CheckConnector

 

It's very similar, but stuff is arranged differently in the fuse box.

Just ran it threw deq and passed I was a little worried because there was some stuff going to the AFM (or MAF, I get em mixed up) that was being used and now aint. Must not be that important.