stuff4mason

Hi guys. Bought a 95 civic LX auto last week. Car started and ran great during test drive. Drove it and started it several times that night. Also filled car with full tank of fuel. Car ran fine. Known issues: gas tank float was bad. It appears to be removed. Hole in exhaust, loud, but driveable. Next day, when to start it and starter cranks, but no start.

I've replaced the battery, replaced the distributor with another distributor, that WAS working on another car. Still no start. Seems to have intermittent spark. cyl 1, good. 2 no spark. 3 good, 4 no spark. Replaced coil, no change. Test coil and seems to have good spark. Replaced cap and rotor and plug wires, no change. Watched several videos on testing igniter and coil. Seems that the negative side of the igniter, with test light on positive from battery should produce flashes, but isn't. OK. Maybe bad igniter. But, also tested injector pulse. No pulse. Replaced fuel filter and pump. I do have good fuel pressure to the filter. However, with all this testing, I continue to have dry plugs. OK. maybe bad ECU, but Honda dealer says they can't test ECU's, and that they rarely fail.

I am at my wits end. What else can I check? I'd REALLY, REALLY, like to drive my new car. Wife is looking at me like, he bought a piece of crap and now its dead in my garage.....

mac25

Buy a Haynes manual.

Find which circuit would commonly effect both the ignition pulse and igniter, then trace each back to the common faulty part.

They should flow like a tree to a common problem.

Example:

Injectors>fuse A>main relay>ecu
igniter>fuse B>main relay>ecu

In this very simplistic circuit set you know that the common segments are the main relay and the ecu.

From there you would check the main relay if it is fine check the wiring. If all wiring and all components except the ecu are functioning then the issue must be the ecu.

stuff4mason

OK. How do you check the main relay? Also, I checked spark again today. Seems its only getting one fire from the coil. Another words, only shoots one spark, then, that's it. I thought maybe cam or crankshaft sensors, but we've cranked on it enough times that if the cam lined up, it would go...I think...

I'll pickup a hayes today. Any further advice would be great!!!

scout206

Not sure if that's your problem or not but there are several you tube videos up on the topic of checking and repairing the main relay. It may have broken solder connections
which may be visible or with a magnifying glass. If you are just installing a new one I
have seen people unplug them, swing the connector over and mount new ones in a more accessible location. Mine is now close to the steering column. Keep it away from any hot locations.
FYI:
The DRL relay is also susceptible to the same kind of solder cracking if they are no
longer working. (Daytime Running Lights) On my 1991 civic you have to pull the glove box out and it's located up behind there on the left side.

stuff4mason

Great info!

Does anyone know if the main relay was bad, would it cause only one cycle of spark? Can I trust a used main relay from the junk yard, or would you suggest to buy a new one? I can't solder for crap.

scout206

I am not an expert on that but my understanding is the main relay has more to do with
supplying fuel than anything to do with spark. I have often just replaced stuff just to rule it out and if you are having spark issues... well you may consider just buying a new
complete dizzy to rule that stuff out too.. Something to think about anyway..

http://www.rockauto.com/en/catalog/h...gle.ca+URL+%2F

ezone

Main relay supplies power to the fuel pump and it supplies power to the ECM.


If you were able to steal a distributor from a running car, can you steal other parts for testing too?

stuff4mason

Well, sort of. A buddy got the distributor out of a 92 civic with manual transmission. So, there are some parts that would work, but the ECM definitely won't work, as mine is automatic. A bad main relay and bad ignition seems to be a theme throughout most of the threads here. Haven't really heard much that ECM's are going bad. Also, tore apart the ECM and didn't really see anything of significance that would say the ECM is bad.

I'm into three weeks of a dead car in the garage. Wife is not happy!!!

stuff4mason

Took out main relay. Appears to be a burn't area on the board. Replaced with a brand new one. STILL no change. Won't start. ERRRRRR

ezone

ECM from the 92, how much of your harness can you get plugged into it? Can you get enough to make the engine run? You don't care about making the trans work right now, just the engine.


Did you get the plug wires correctly ordered around the distributor cap? That's quite important.


Compression, spark, fuel. Which can you prove is not right?
Dry plugs says no fuel.....
Got a spray can of carb and throttle cleaner? Spritz a bit into the throttle body and crank it over, see if the engine will fire. That would prove a fuel problem at least and give you some direction to go with this..

stuff4mason

Fire is the biggy. Last night I bought a new distributor from Advance. $156.00 later, still no spark. Zero. As far as plug wires, I am pretty sure they are correct, although we are basing that on where the wires were, when it was running. Besides, if they are wrong, I should still have spark coming to the ends of the plug wires. Also, continue to have no injector pulse, so no fuel either. I think the only two things that are possibly left are the ECM or the ignition. We will tear apart the ignition today and see if we can bypass it. I like your idea on the ECM. Might have my buddy stop by and grab that, see if it does anything in the car.

scout206

I was changing and testing all kinds of stuff to try to solve the surging at idle problem
and after finally buying a compatible ECU from another Honda the surging is now almost non existent. Sorry to hear the new dizzy didn't solve the spark problem..
but at least you know you have replaced the bulk of your 21 year old ignition system with new components. Have you tried testing for spark at night with a sparkplug clip tester attached to a secure ground... ZERO?
I think there are a few sensors that supply info to the ECU, >> MAP, TPS, CTS, some have basic resistance tests you can try with a multi meter including the injectors to quickly see if they are in range. I see all those specs printed in my Haynes manual.
Hope you get a chance to plug in another ECU. Good compression? Good plugs?

stuff4mason

Yes, the car's in the garage, with light off, no spark. Picked up a Haynes today. Brought home two ECU's. First one, off standard car, wouldn't even make fuel pump prime. Second one, matches my car, Worked. Well, it primed the injectors, and the single Check engine light (by shorting the ODB1) went out. Still no spark. No spark at coil. Both of the ignitor wires tested positive for power. But, no pulse. (remember, new distributor) Brand new plugs. Good compression, although we did not check it. Plugs in correct order, and at t.d.c. Not off by 180. Took ignition apart too. Starting without key now to bypass. No change.

scout206

I am sure you may have likely searched these... but I found quite a number of YT videos pertaining to no spark in Honda diagnostics... could be worth a closer look.
You obviously need to get those plugs firing!

If you have power at the igniter and no spark from the coil you are probably getting close to your eureka moment! Keep in mind that just because it's a
"new" dizzy doesn't mean it is a working one... I have read about people
have to exchange them more than once...

EF Hatch it man

I just changed out all the capacitors in my ecu today and it is running great. C21 and c24 were bad. And the idle smoothed out too.
Mine was keeping the cel on for about 30 seconds till it let the fuel pump on. And after it started the cel came right back on. Now the fuel pump comes right on and the cel never came on.
It was a bit of a challenge to get the caps out and holes cleared but there's nothing better than having a plan come together!

Also used a squirt or 2 of electronic cleaner in the ignition switch. Ran the key in and out a dozen times, waited 5 minutes then went in with 1 squirt of wd40. This helped initiate the start process too. So the old adage fix one thing to find out what else is broke.

scout206

Nice!
This is a touch off topic but a few years ago my computer monitor packed it in. I did a little research on YT and found they are kind of designed to do that due to....
capacitor failure. I am not an electronics expert but wanted to try it before I bought a new one... 20 minutes to get the board out... took it to en electronics shop and bought the 4 or 5 capacitors I needed for about 10 bucks >>> 20 - 30 minutes to swap them out and put it all back together.
Still using that monitor today. I bet 90%+ of people would have just tossed it and bought a new one lol. So, it's good to know how to change capacitors as they do fail.

stuff4mason

Well guys, guess what? SHE'S ALIVE!!!

There's nothing worse on these forums then when someone asks for help, people give all kinds of advice, and once its fixed, doesn't bother coming back to the forum to explain what the problem was for future people!

So, First off, we changed distributor four times, plug wires, new plugs, new cap, tried three ECU's, replaced main relay, new battery, tore apart the ignition switch, replaced the fuel rail, and replaced the injectors!!

The main problem was we were getting spark but it was very weak, and only on two cylinders. The other two seemed dead. Last night my other buddy came over and started grabbing the wire harnesses all over the engine. When he grabbed the harness below the distributor, something changed. We took off and replaced the main grounds at the tranny and the engine. My other buddy found another ground just below the distributor and realized the little 10mm bolt that held that ground to the thermostat housing was loose. We tightened it, and WAM!! Car started right up!!!

Put it all back together and drove the crap out of it. Ran perfect!!! In fact, it ran much better than it did when I bought it. SO EXCITED!!!!!!!!

Thank you all for your input and help on this thread. I've got a BMW that I work on and have to ask for advice on one of those forums. Its totally refreshing dealing with Honda people versus stuffy ***, know it all Beemer people!!!

EF Hatch it man

Ya Mason if you own a civic you like people, period. And myself i like sharing exp. and talking cars.
Really hard to meet a car snob here, right guys.
Just like sharing the ecu repair. It'll help someone who likes repairing instead replacing. And saving a buck or 2. To uses on another project, lol.
O ya taking the board to an electronic shop is a great idea its a lot of tools to have to diy.

Thanks for the good idea!

scout206

Congrats on getting things running again and your follow up report!!
That was great to hear!!!

I have been restoring a 1980 International Scout for a few years and have replaced all the floors and on and on and on. The Civic has just been kind of
a spare car but it's easy to get used to that fantastic gas mileage!!
No comparison to a 345 engine and it's even better than my motorcycle!

Re the electronics shop, I just went there to buy the caps, and took them
home and replaced them. A small soldering gun, flux, thin solder and maybe a magnifying glass isn't that expensive to add to your DIY tools or as you
suggested you could likely hire them to do it as well but you may need
to wait and make two trips... also lots of help and tips on YT.

I suppose in hindsight after reading what happened, if somebody else is struggling with a no spark condition, a quick continuity test from the negative side of the coil to the negative battery post may help to identify
the problem as a grounding issue...for the few seconds it takes to do it.