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not firing on # 2 and 3 cylinders

Posted by joe sobo, Sep 26, 2009
Newbie Forum - Beginner DSM modification questions and discussions. Common, repetitive, and general discussions will get dumped here from other tech forums. Unless you're a Probationary member you shouldn't post threads here.

  1. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    i just did an engine rebuild . bone stock 95 gsx. there is no spark to 2 and 3 plug wires. i rried new coil pack, and transister. neither helped. i search and found no answer. 1 and 4 i have spark. someone please point me in the right direction
     
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  2. Helifax

    Helifax Proven Member

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    Did you reinstall the CAS? I'm in the same boat as you and I forgot to install the CAS so I'm waiting for it to come in the mail as I can't find it.
     
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  3. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    well. i switched out the ecu and got it to run. but the problem now is that it will only run for 3 seconds, then shut off. but i had a bright idea to switch the ignition on and off right before it stalls and i can keep it running by doing this. as soon as i stop turning the ignition on and off the car will shut off 3 seconds later. any help, please guys, before i torch this one
     
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  4. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    yes, i never took it off the head, cause the head was rebuilt by me two months before rebuild
     
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  5. Helifax

    Helifax Proven Member

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    Hmm well maybe it's not connected right but if the cas isn't the problem then the next thing I would check would be the ptu but you replaced that so I'm thinking ecu? I'm not sure as I'm having what seems like the same issue and I'm hoping that installing the cas will fix my problem but if not then I'll need some of the more experienced dsmers to chime in.
     
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  6. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    someone said on another thread that you can reset the ecu,? is that just unhooking the battery?
     
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  7. Helifax

    Helifax Proven Member

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    Yes disconnecting the battery for about 10 minutes should reset the ecu.
     
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  8. Helifax

    Helifax Proven Member

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    Wait so after swapping out the ecu do you have spark in all 4 cylinders?
     
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  9. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    yes, i swapped the ecu and now have spark. it starts right up but shuts off 3 seconds later unless i keep flicking the key on/off position, and it will stay running until i stop doing that
     
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  10. Helifax

    Helifax Proven Member

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    have you tried resetting the ecu?
     
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  11. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    yes, i tried resetting it, but i cant seem to keep the car running more than 3 seconds.
     
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  12. Helifax

    Helifax Proven Member

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    Could it be a bad fuel pump/injectors?
     
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  13. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    no, cause the pump stays on, and the injectors were fine before the rebuild, and i never took them off of the head
     
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  14. 94dsmgsx

    94dsmgsx Proven Member

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    Was it shutting off every three seconds with the other ECU in there? If not then, is the ECU that you have in there now old or new? It still might be a problem with the ECU caps leaking if your using an older ECU.
     
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  15. chadnum1

    chadnum1 Proven Member

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    Marysville, California
    Ive had this happen on 3 different dsms, the cam sensor behind the intake cam gear gets a small crack in it and brakes signal, probably has nothing to do with your rebuild just old age LOL.
     
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  16. blcknspo0ln

    blcknspo0ln DSM Wiseman

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    Central, New_Jersey
    Agree, it sounds like you have a break in the wiring somewhere. Did you drop a 6 bolt in? If so, I would go over the 1G cas wiring you had to do.
     
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  17. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    well, the 95 eprom ecu, the car only runs on cylinders 1 and 3. if i put the newer 97 in there, the car just shuts off after 3 seconds.
    but when i put the 97 ecu back in its original car,it is fine with no issues. i also tried the 95 in the 97 car, and it runs on all four, but the car wont rev past like 3,500 rpm
     
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  18. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    no, i didn't do the 6 bolt swap. just a fresh rebuild on stock engine. the thing i dont understand is that before i did this rebuild, the car ran fine but started to get a knock. now that i'm done, 1 ecu give me two dead cylinders, and a known good working ecu gives me great performance for 3 seconds
     
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  19. chadnum1

    chadnum1 Proven Member

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    firing order changes between the 95 and 97 years so plug wires need to be swapped, Im telling you man its the cam sensor behind the cam gear on the intake cam, make sure its plugged in otherwise its shot. if transistor is good this is what causes your problem.
     
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  20. chadnum1

    chadnum1 Proven Member

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    the ecu from the 97 isnt giving u full performance its just sending a spark to a plug one on each coil causing and up and down affect causing it to run and then the sensor stops reading and it dies. your 95 computer is sending spark to the same coil causing it not to start. Its your cam sensor
     
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  21. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    so that would make the car run on only 2 cylinders?, and when i put a diff ecu, it has a different problem?
    btw, i appreciate the advice guys. i'm not saying that you are wrong, just trying to understand my car a little more for the future of me and my toys LOL
     
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  22. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    yea, i tried a transistor off of my 97 and no change. and i put the 95 transistor on the 97 and it is good
     
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  23. chadnum1

    chadnum1 Proven Member

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    Marysville, California
    the 95 and 96 cars used a cam and a crank sensor set up that worked opposite of each other if the cam sensor goes out youll be on 2 cylinders, changing the ecu changes the firing order which would make it run on 2 cylinders but one up stroke one down stroke but as soon as the ecu gets no read from the cam sensor it shuts down. Cam sensors like 80 bucks but you gotta redo the timing belt when you do it.
     
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  24. joe sobo

    joe sobo Proven Member

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    stuart, Virginia
    so the easy way is to put a 1g cas in my car so i don't have to pull the timing belt apart?
     
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  25. chadnum1

    chadnum1 Proven Member

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    Marysville, California
    yea valve cover comes off install cam sensor and wire it in according to vfaq.com
     
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