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-   -   92 civic engine cranks but it won't start! (https://www.askmehelpdesk.com/showthread.php?t=28327)

  • Jun 18, 2008, 09:38 PM
    Doug777
    Yeah... the first row of numbers was the same. I figured that was all that mattered. It came out of a working 92 civic 1.5liter manual tranny. It worked perfectly for a bit before crapping out on me.

    As far as the dielectric grease goes, can I get that at autozone or do I have to go somewhere special? I can try it but I'm still pretty sure that something electrical has to be going wrong as well.
  • Jun 19, 2008, 08:31 AM
    TxGreaseMonkey
    I'm concerned the replacement ECM is not an exact match and that is the heart of your problem. Dielectric grease is available at almost any auto parts store.
  • Jun 20, 2008, 12:18 PM
    Doug777
    So here's my plan for now. I'll probably end up buying a new/reman ECM, but first I'm going to try to fix several of the electrical issues that I already know are there.

    One, the cruise control tries to turn on then doesn't stay on.
    Two, the door locks quit working a few weeks ago
    Three, there is something loose in the wiring for the dash lights. They didn't work at first, then they did for a day, then they didn't work any more after that.
    Four, the horn doesn't work.

    The fact that I get shocked every time I get out of my car makes me wonder why, since that's the only car I get into that I get shocked from... and it makes me think something electrical is goofed.

    Now I'm not super knowledgeable about car computers, but I do know that with desktop computers one part can at times cause other parts to go bad. Maybe you could shed a little light for me about how the car computers interact with a short to ground and stuff like that... and also something about that shocking problem, if introduced to a microchip will fry it. I am not going to buy a new ECM without getting some of this fixed to begin with.
  • Jun 20, 2008, 05:53 PM
    TxGreaseMonkey
    Doug777, you need to eliminate stray current from damaging your ECM. That was part of what the recommendation to use dielectric grease was about. Try isolating what circuit the stray current is flowing through and fix the problem. The link below may give you some ideas on how to proceed:

    https://www.askmehelpdesk.com/cars-t...tml#post241804

    Even static electricity is a threat to ECMs, which are full of microchips and other sensitive components.
  • Nov 10, 2008, 10:44 AM
    xxfile

    Hi, I have the same problem with my 92 civic. I was giong down the highway and the car suddely lose throttle. I towed the car back home, I check for spark, no spark. I replaced the distributor, and now I have spark, but it doesn't start. I checked the MFR, it works, when I turn the key to on, I can hear the fuel pump. So what does the problem seem to me? Could I have a bad map sensor? Or could I have a bad ECM?
  • Nov 10, 2008, 11:04 AM
    TxGreaseMonkey

    xxfile,

    . Check for a broken timing belt.
    . Check each cylinder's compression.
    . Clean main ECM ground on the thermostat housing.
    . Perform K-Test on ECM.
    . Test all under-dash and under-hood fuses with a test light or multimeter.
  • Nov 10, 2008, 12:26 PM
    xxfile
    So I know timming belt is fine since I can rotate the crank-pully with a break bar and the camshaft will rotate

    How do I check cylinder compression and K-test?

    Where do I find the main ECM ground on the thermostat hosing (if it's in the hayens manual, Ii can read it)?

    I'll test the fuses after work today and come back w/ more questions. Thank you. ;)
  • Nov 10, 2008, 12:29 PM
    xxfile

    Well, I just realize you have a whole how to posts. I'll read them first before I ask more questions.
  • Nov 11, 2008, 07:11 PM
    xxfile
    Quote:

    Originally Posted by txgreasemonkey View Post
    xxfile,

    . Check for a broken timing belt.
    . Check each cylinder's compression.
    . Clean main ECM ground on the thermostat housing.
    . Perform K-Test on ECM.
    . Test all under-dash and under-hood fuses with a test light or multimeter.

    Hi txgreasemonkey,

    So I did what you said.
    -Timming belt is good,
    -I don't know how to check cylinder compression with the tools I have, but when I take one sparkplug out and check for spark, I try to stuff the hole with paper towel and it shoots the paper towel right ouw, I don't know if that means I have compression
    -I don't know which one is the main ground exactly, but I looked for all the grounds and clean them, they seem good.
    -I have 5V between the yel/grn and the blue wire (left pin and middle pin)
    -I didn't find any broken fuse, I especially check for fuse 24, because it controls the MFR and ECM, but that one is good.

    Does this leads to off timming when I did the installation? And how do I check for timming?
  • Nov 11, 2008, 07:17 PM
    TxGreaseMonkey

    xxfile, I'm not sure what else to suggest. Could you have blown the head gasket, for instance? Maybe someone else will chime in with additional ideas.
  • Nov 11, 2008, 07:38 PM
    xxfile

    Do you think it can be timming issue? Because when I crank, if I hold the key long enough, I would hear back fire (like that bomm noise when you have unburn fuel in your exhaust)
  • Nov 11, 2008, 07:42 PM
    xxfile

    And if I have spark, then we can basicall rule out bad MAP sensor right?
  • Nov 11, 2008, 08:03 PM
    TxGreaseMonkey

    Yes, MAP Sensors are very reliable (and very expensive). I don't think it's the MAP Sensor at all.
  • Nov 11, 2008, 10:10 PM
    xxfile

    So how do I check timming? Because I thought I the distributor can only go in two directions, and one directions is 180 degreess off. So given that timming belt isn't broken, the timming shouldn't be off right?
  • Nov 12, 2008, 01:41 AM
    xxfile

    So if anyone can help, please do so, here's a list of what I have done so far:

    So... Here's what I have done so far.

    Check spark: I took the spark plug out and then ground it, when I crank, I can see that it has spark. This also tells me that map sensor is good.

    Check compression: I didn't use a gage, but I stuff paper towel into the top of the cylinder when I check spark, and when I crank the car, it shoots right out, so I assume I do have compression and it's probably good?

    Check ECU: I did the K-test, which is, taking out the map sensor and check for 5 volts between ground and it's power (yel/grn and blue). I did have 5 volts.

    Check for exhaust: I once ran into a problem when I was in an auto shop that a car had a bad cat-back and it stuffed up the exhaust and hence the car won't start. I took out the two bults between the down pipe and the cat-back and try to crank the car, no luck, and besides that, I smell gas, so I'm assuming it's spraying gas into the cylinder?

    Check voltage on fuel injector: I checked the voltage between the fuel injectors, I got 4 volts when the key is on. I'm not sure whether it's right, but given that when I check for exhaust, and I can smell gas after cranking the car, I assume the fuel injectors are good?

    So at this point I guess it' leads to timming? So does anyone know how I should check timming? I mean... is there a way to check if and totally off timming and the car won't start?
  • Nov 12, 2008, 06:26 PM
    xxfile

    Yo txgreasemonkey, question for you. I just tested the ECU, like I jump the ECU test terminals (the one with two wires), and the CEL staied on, no blinks, so I did the map sensor test again (last time I only test the yel/grn and grn wire) so I still have 5 volts between yel/grn and grn wire, but I don't have any voltage between the what and grn wire, so does that tell me my ECM is dead?
  • Nov 12, 2008, 06:38 PM
    TxGreaseMonkey

    Xx, your ECM is likely good, if you performed the K-Test properly and it indicates 5 volts. Be sure to run the test, as I described it. I'm not sure you did it properly. The red wire of your DMM goes to the reference wire on the MAP Sensor connector and the black wire goes to ground.
  • Nov 12, 2008, 06:52 PM
    xxfile

    So I put red terminal on to the middle (green) wire, and red on yel/grn and white? Like I have to check both wires right?
  • Nov 12, 2008, 06:58 PM
    TxGreaseMonkey

    The K-Test: Remove the MAP Sensor connector and turn the ignition switch to ON (not start). 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.
  • Nov 12, 2008, 07:07 PM
    xxfile
    Tgm, I just went down and tried the test real quitck so here's what I did:

    Voltage between yel/grn(+) and grn(-): 5volts
    Voltage between white(+) and grn(-_: less than 1 volt
    Voltage between yel/grn(-) and grn(-): - voltage (I can't see negative how much, but it's negative)
    Voltage between grn(+) and white(-): no voltage

    I tried the same thing using battary ground, and I have the same result. I jumped the terminal for CEL codes (the two terminal connector with the grn/wht and brown wire) and the CEL stays on

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