runin on 3 cylinders :( help ME!!!!

[FallbrookS13]

hey guys, just picked up another fastback. its only got 70k on the the motor. its a ka24de. only bummer is im only running on three cylinders. haha. the reason i got this car is cause it was a low mile twin cam...thinking "yes i can finally get away from that 12 valve single cam." but now im still stuck with only 12 valves for the moment hah!
k here is what i did
i pulled out the spark plug cable... in the number 1 cylinder...and nothing happend. it didnt effect how the car was running at all. let me add that the motor idles ruff.
k so obviously something is wrong if nothing happend when i pulled up the spark plug cable.
so then i swaped the number 1 cylinder spark plug cable w/ the number 2. figuring that if my same issuses happen to the #2 cylinder then it would mean i have a bad spark plug cable....of course it didnt prove to be the problem. at least that a bad cable is elimnated
so then i unplug the fuel injector for number 1 cylinder while hte motor is running...nothing happens......
so i got a good injector and replaced it. and still didnt solve my problem. i checked to see if power is being sent to the fuel injector plug and it is...sooo... i dunno
i did a compression test and got 150 all the way across....so that is good at least.

IF ANYONE COULD HELP ME OUT ON SUGGESTING ANY MORE ADVICE I WOULD APPRICIATE IT A LOT, thanks!

[uiuc240]

new plugs
new cap and rotor
reset ECU
new fuel filter

those are all easy and cheap to try

[Uniac]

you are getting a full 12 v to the fuel injector? My SOHC did the same thing a while back and the computer had shorted out and #3 wasn't firing.

Check your rotor cap, put an extra plug in #1 plug wire and check for spark. Also it could just be a bad conection on the fuel injector. Try wiggling it around and see if it makes a difference.

I bet it's a injector problem, if you swapped plug wires from 1-2 then it has to be fuel. But double check spark first.

Hope this is any help.

[mjjstang]

check everything that those guys said but my friend had this prob. we took the head off and found there was a piece of metal stuck in the intake or maybe it was exhaust valves, so when one was open the other tried to close and couldnt then the same w the other so they never closed completely and it messed things up, but then again, wouldnt you get like no compression if they were stuck open, hmm i dont know but my friend had these same symptoms.

[giant killer]

not to jack the thread.. but what does it take to "reset" the ecu?

[West]

I would do what Uniac suggested and test the voltage of the Injectors with a voltometer. My car was doing the same thing and I figured it was the injector anyways, although after I removed them I found that 3 of the inectors were unuasable.

[FallbrookS13]

to test the voltage of the injector should i tap into the wire while it is still hooked up to the injector or unplug it and then test it ? am i looking for a solid 12v signal?
thanks
anDrew

[FallbrookS13]

and...say i am recieving power... or im not. what does this mean what would be the next step? thanks

[FallbrookS13]

i just replaced the cap and rotor, and checked for voltage to the injector and i am getting full power to the injector....this sucks. hah. what now? anyone have any sudgestions.

[Uniac]

ok, try the same thing you did witht he plug wires with the injectors, swap #1 and 2 see if that makes a differance.

Stupid question, did you check the plug itself?

[FallbrookS13]

yeah i replaced the plugs. and i put in a new injector. one from a car that was running...so i dont think i need to swap the injectors. thanks though.

[Uniac]

not swap the injectors, the injector wires, see if that makes a difference. Like put the #2 wire on #1 see if #2 dies. If it does, you know where the problem is.

[FastBack 240]

My car has seem to been doing the same lately. Not very often though. Sometimes if I am in second gear at a 10 mph roll and take off, the tach is at about 1200 and it will sputter on 3 cylinders and once I hit 2000 it takes off back to normal running strong on 4 cylinders. I first though it was a clogged injector but then added a bottle of cleaner to the fuel and didnt do much. Im thinking its the MAF that is dirty and will clean that tomarro. Any other idea's? Doesn't even fuck up in first when starting from dead stop. Only in second at a 10 roll. Im confused.


P.S..... My car did the same a while back and as MJJ mentiond it was a metal chip that came from somewhere either dropped in the hole accidently when changing plugs or a chip from the motor but it got logged in between intake and exhaust leaving both open and a peice of shit motor situation. Do a search cause some other memebers had the same problem with metal being logged in the same place. :wtf:

[FallbrookS13]

fuck, this whole metal being lodged in my motor idea is starting to scare me...i hope that is not the issue...but if it was keeping the valves open i dont think i would be getting 150 on the compression test of that cylinder.
UNIAC, would that be safe to swap the injector plugs considering the spark fires in a certain order, and the injector pulses in a order which is all in unison as to how the motor rotates and the pistons position.???? (that was really hard to express haha, sorry if it makes no sense at all)

[DuffMan]

Are you sure you are actually getting the injector signal to the injector. Connect both terminals to both probes of a multimeter and you should see some voltage or pulsing twitches, even at idle.

Also you can check to see if the injector is opening by putting the tip of a screw driver on the injector and holding your ear to the handle. Its kind of hard but you would be able to tell the difference between a working one and non-working if you listen carefull and can distinguish the clicking from the general engine nosie.

If you get no signal to the injector, it could be a broke wire, shorted wire, or short in the ecu.

[Uniac]

fuck, this whole metal being lodged in my motor idea is starting to scare me...i hope that is not the issue...but if it was keeping the valves open i dont think i would be getting 150 on the compression test of that cylinder.
UNIAC, would that be safe to swap the injector plugs considering the spark fires in a certain order, and the injector pulses in a order which is all in unison as to how the motor rotates and the pistons position.???? (that was really hard to express haha, sorry if it makes no sense at all)

i don't see why it would be any different than swapping plug wires for a few seconds, it's not going to harm anything if you only do it for a few seconds.

Give it a try and see how it goes. I've run the SOHC like that for a week, stupid #1 wire wouldn't work on #1 injector, but it worked on #2....got to get to school somehow right?

[FallbrookS13]

Duffman, yeah i've already done those things, thanks for the sudgestion though. i am recieving power to the injector and i listened to the injectors w/ the screwdriver. that was like the first thing i did.
Last night i was thinking and i remembered something that i think is what my problem is. the day i bought the car i replaced the spark plugs. (note: i didnt realize the car was runing on three cylinders until the day after i bought it, dont ask why ahha but i know it has been like that sincei bought it cause when i picked it up from the ladys house the motor was idling all ruff like it sitll is, i just figured it was a ruff idle) so right after i bought i went to replace the spark plugs and i remember that #1 cylinder was really tight. the spark plug was really really tight. at the time i didnt think anythingn aboutt it. and i also remember that it was a lil tight when screwing the new spark plug in. not so tight that it felt like it was being cross threaded just a lil ruff. so now i think that whoever put those spark plugs in that i took out fucked something up cause it was way too tight. who knows what exactly happend though. i guess im going to have to remove my head and see what the fuck is up w/ it.

[FastBack 240]

yea my car is officially fucked as well. Idle is fucked and certain throttle positions an injector cuts out. Sucks ball's cause Mon was going to drive back to MI. I am still possibly gonna get back somehow and take the injectors off my SR sitting in my garage. Dont know if it is injectors but certain throttles as mentiond one cylinder takes a dump and runs on 3. Times like this when I hate my car. :rant2:


Does this sound like a fucked injector or does it sound like something else to you? I first though it was dirty maf but it only does it to one cylinder and at certain throttle points. Also im burning oil. I think its time to finally drop in the SR. Lets just hope I didnt buy a dud SR. :x:

[DuffMan]

To get good compression everything in the head has to be working. Spark + fuel + compression = combustion. I still think you are missing spark or fuel.

[Uniac]

i agree with duffman, a head job is more work than you want to get into.

You got a freind with a dohc s13? just steal his ecu and see if it makes a difference. If it does, i got an extra one right next to me.

pop the valve cover, and check to make sure the valves on #1 are actually opening. It's worth a shot and alot easier than pulling the head. Hand crank it tho, unless you like cleaning oil up.

[CustomS14A]

I bought some denso,s and for some reason two of them broke in half...
made my car run like shit thought it was something else but it was one of the little things...

[FastBack 240]

Any answers to my question? Should I go ahead and change injectors?


I know its not mechanical or electrical because it only does it at certain throttle positions. Tomarro I am gonna go the the junk yard and get a set of injecters and see if it makes any diffrence. Other then that dont reallly have a clue. I can unplug them and it will really make a diffrence but dont really know which one sucks. Also changed plugs today thinking it may have something to do with that and the plug in cylinder one was black while the others were tanish white. :rl:

[FallbrookS13]

Just to put some closure to my issue.
i finally figured it out what the deal w/ and now everything is great. that number 1 cylinder injector was staying open. as soon as i turned to key to the on position it started pissin fuel. there was so much fuel in there that the spark wasnt doing shit. i pulled out the plugs and cranked over the engine and fuel was squirting out of hte cylinders like crazy. did that for a while to get that stuff out then put in new injector, and spark plugs and changed my oil... let it run for a while to burn off all the unburnt fuel in my exhaust. it smoked like crazy for a while. but now everything is great and the engine runs so smooth. its actually pretty strong. thanks for all ur help guys. take it easy

[DuffMan]

Heh, be glad you didnt hydrolock.