No Spark, how to check ecu??? PM5
 

So here's the deal, i sold my 300,000 mile 1989 civic dx sedan to a neighbor (first mistake selling to your neighbor) running like the day my parents bought it except looked like it went through 2 led foot sons and sister who burned up 2 clutches :l (now she drive a 2006 sti and has mananged not to burn up a clutch in a long time.) So it's as ugly runner but it ran. SO unluckly i run into him and he says it's stopped running so the nice guy that i am went to check it out. NO spark. Fuel pump primes, no fuses blown, ecu has power, voltage at dizzy, have a know good dizzy and still no spark, all checks are good at dizzy and wires good from dizzy to ecu, grounds and ground straps good. So all signs point to a bad ecu which is the original one. So my qustions is, did i miss anything, and if not, how can i actually check the ecu? I know i won't find that in any repair manual. I would like to try to find out what is actually wrong inside the computer. It is a PM5. Maybe i won't be able to check it, but i wanted to atleast try before replacing it or find out what area in the ecu. I opened it up (ecu) and there is no smells and i see nothing visually unless i missed something. Please help genius ones!!! :1 please teach me!!

Re: No Spark, how to check ecu??? PM5
 

man just goto the junkyard with the bad one and tell them you are bringing it in to find the same one. they will mark it and the just switch the boards out with a different one in the old case and tell them you could not find the one you needed. its free and all you need is a 10mm socket, ratchet and a phillips screw driver. or just go buy one from the junk yard for 20 dollars

Re: No Spark, how to check ecu??? PM5
 

You're right! I will hit the junk yard, although i think they are more then 20 used. But i still want to learn about the circut board.

Re: No Spark, how to check ecu??? PM5
 

Man check the coil first(in the distributor)............they are pretty common faults for no spark.

Re: No Spark, how to check ecu??? PM5
 

Ignition Coil Resistance

1. Remove distributor cap. Remove 2 Phillips screws retaining primary ignition leads to ignition coil. Remove primary leads
from ignition coil. Using an ohmmeter, check resistance between primary terminals "A" and "B" on ignition coil. See Fig. 1 .
Resistance should be .3-.5 ohms at room temperature.


2. Check secondary resistance between terminal "A" and secondary output terminal (coil tower). Resistance should be 9440-
14,160 ohms at room temperature. Replace coil if readings were not within specification.


Fig. 1: Ignition Coil Terminal Identification

https://i62.photobucket.com/albums/h...ivicdistro.jpg

Courtesy of AMERICAN HONDA MOTOR CO., INC.
© 2007 Mitchell Repair Information Co., LLC.
BASIC TESTING -1989 Honda Civic DX Page 1 of 1

Re: No Spark, how to check ecu??? PM5
 

Hey thanks for all the info. I have 2 good dizzy'z and 4 coils. At first i thought it was the igniter in the dizzy but i put in a known good dizzy, still no es sparky. Ihave done those exact checks from my haynes manual. I have a fluke 87 so it should be pretty darn close, i hope so for 325 bucks off the tool truck like over 5 years ago. It came off the Cornhole truck, he was cheaper then matco, mac and snap-off. I miss getting on the tool trucks and seeing all the toys. I don't miss the payments though.

Re: No Spark, how to check ecu??? PM5
 

You didnt mention anything about the main relay. Is it clicking when your flip the key on? You can take it out and check the solder joints, make sure there are no circular stress cracks, aka "Dry Joints", if so reflow the solder as necessary. Here's a good article http://www.tegger.com/hondafaq/mainr...mainrelay.html

Re: No Spark, how to check ecu??? PM5
 

Yeah, the guy who bought it already replaced the main relay, its got a brand spankin new one in it and the old one was still in the car. I swapped the new one out and put the old one in it. IT was still running with the old one whenn i sold it. I am out of town now but when i get back i will fix it and let ya know what was the issue. :8

Re: No Spark, how to check ecu??? PM5
 

Broken timing belt?

Re: No Spark, how to check ecu??? PM5
 

hopefully he wouldn't have missed something that obvious. I assume the car just didn't start one morning.

I would swap ECUs myself, but I usually have a couple laying around.