KA24DE intermittent rough idle, hestitation, PLEASE HELP!

[jarredd]

Car:
1993 240sx KA24DE

Recent maintenance (approx 8-10 months ago):
spark plugs
wires
valve cover gasket
1 failed fuel injector
(It was scheduled for an oil change this weekend also)

Problem:
Drove to work about 6 miles, no problems. Drove during lunch, no problems. After work, got in and turned the key and it had a rough start and was shaking and bogging down. The RPM seemed to stay steady, stuttering up and down slightly. But the car shakes violently. I turned it off and looked under the hood and noticed that oil was seeping from the valve gasket. Checked the oil and it was nearly bone dry. I limped it down to the nearest gas station (about 2 miles) and put two quarts of oil and some Techron fuel treatment in it. It seemed to help for about 30 seconds. Then began to shake bad again. I limped it the rest of the way home. As I drove it home, I noticed that the car seemed to have some hesitation/drag from idle up to about 2500-3000 RPM and then seemed to have a little more power. I didn’t push it for fear of making it worse. As soon as I got home I started to check under the hood.
Pulled each spark plug, they all look good.

Pulled each plug wire while the motor was running and cylinder# 3 had no effect (the others nearly stalled the motor, so I know they are ok). I could hear the wire ticking, so I know it was firing.
I then pulled each injector plug one at a time, #3 had no effect (the other nearly stalled the motor). So I thought that it could possibly be the injector is clogged/bad. (as mentioned above, I had #4 injector go out about 10 months ago, so I thought this was a similar issue). I replaced the injector and the car was purring smoothly for about a minute, and then shaking again. Now it is not as constant, but more like an intermittent stutter.

I pulled the injector plug for #3 again and no effect on the motor. Still shakes. When I pull plugs on the other cylinders, they all make it worse. So it seems that everything is pointing to cylinder #3.
I cleaned the MAF with cleaner for good measure and checked the grounds on the chassis, which seems to be making good contact.
I am gonna try to get an Ohm meter and test the injector plug to make sure it has not gone bad. Does anyone know what the resistance value should be? Do I test while the motor is running or off?
Could it possibly be a bad/bent valve? I would think it would be more consistent is it was, because it starts up fine and idles high (approx 1200-1500) for about 30 seconds then gradually drops and starts to shake, then smooths out for about 10 seconds, then shakes, then smooths, etc...

Any other suggestions are greatly appreciated! Thanks in advance!!!!!!

[jarredd]

morning bump, please help... i have read through the forums and cannot seem to find any answers

[Sam_Well.13]

you want to try cleaning your TB or IACV. my car is doing the same thing, ive checked everything besides cleaning the IACV...

and my N/A SR had a very similar problem to yours, would actually sputter and choke when i floor it until i pass 3500RPM then would jump through RPM no problem, clean the IACV and all connection and it was good to go.

goodluck. maybe you can also swap injectors from a friend to determine it IS your injectors.

[jarredd]

you want to try cleaning your TB or IACV. my car is doing the same thing, ive checked everything besides cleaning the IACV...

and my N/A SR had a very similar problem to yours, would actually sputter and choke when i floor it until i pass 3500RPM then would jump through RPM no problem, clean the IACV and all connection and it was good to go.

goodluck. maybe you can also swap injectors from a friend to determine it IS your injectors.

I'll give it a try cleaning the IACV. i replaced the injector on #3 and it didnt make a difference. I ran some seafoam throught the gas tank and oil fill spot and it seemed to help a little. I started the car last night after it had sat with seafoam for about 2 hours. It was running nicely and i drove it up and down the street :2f2f: with minimal hesitation. Now it runs smoother for about 2 minutes, then starts to hiccup every few seconds, then starts to constantly shake.

I'm going to pull the plugs and injectors one at a time again while it is running and see if it is still happening with #3 cylinder.

Thanks for the tip! :x:

[JDMRIDDAZ]

:mepoke:hey i wrote a special thread about the plauge of the s13 chassis...
it helps
s13 chassis gremlins - SFLDrifters.com (http://www.sfldrifters.com/forums/showthread.php?t=65978)
check it out ive had ka's and 3 sr's..
most of the time its power to the ecu or sensors..
like iacv...o2 sensor..fuelpump cicuit...

[jarredd]

can anyone explain why when i pull the injector plug or sparkplug wire on cylinder 3 it makes no difference. Could it be that i am not getting compression on that cylinder? I still need to test the compression, but i took off the IACV and it was not even that dirty. cleaned it, reinstalled and made no difference.

[smoked240]

Check if your getting power to the #3 injector.

[supreme_1]

yep check for power to the injector, the red i believe is constant and the other color is the pulsating signal. it could also be the injector harness, try and wiggle it around on the injector and pull and tug on the wire going into the injector clip. if that doesnt work try and put constant power the red wire and jump a pulsating signal from another injector to see if it runs any differently. if it does then its most likely your injector harness. otherwise try and check your ground wire for your injectors, i believe its the one on the front pass side of the head. i dont remember correctly but try and shake it around or reground it. lastly if all else fails, shake all your wires in that loom which runs along the head and see if that changes anything. if it does, then u got a short or cracked wire somewhere.

if all else fails your ecu is bad.

make sure u have spark too

[Super_OK_S13]

i'm having the same issue but mine starts up and idles fine for like 30 seconds or so, then rpms drop and my a/f guage goes rich and the engine sputters and shakes but does not smooth out... checked compression, 125-135 on the guage in all cylinders. spark is there. i also switched wires and the problem didn't follow. also had the injectors pulse tested and air blown through the rail to check for o-ring leaks. nothing... hope you fix your car...

[nismo_enthusiast]

Was this problem solved yet?

My GF's 95' S14 is doing the same exact thing but in Cyl #1. I have moved spark plugs/injectors and the problem does not follow. I have also checked gap on the plugs and verified spark on all ignition wires.

If I remove ignition wires, there is no change to Cyl #1 but the others stall out the motor. Same thing with unplugging the injectors.

I don't have a compression checker but I pulled the valve cover and turned the motor until Cyl #1 reached the top of the compression stroke (verified by watching cam lobes) and when I begin to loosen the spark plug the air pressure sneaks out passed the plug so I know there is at least some amount of compression in Cyl #1.

I don't get it... How can it have intake, fuel, compression, and spark and yet seem to be not functioning at all in only 1 cylinder? I'm so confused!!!

[p3t3y18]

i myself is having exact problem... car turns over fine idles fine for bout 30sec to a minute and then starts to shake bad BUT my rpms stay steady bout 800... i checked maf, changed o2 sensor, changed injectors and nothing still doing same thing... in my car wen i pull plug number 4 it does only a little difference.. wen i rev or gas car to drive off it bogs a bit between 2k to 2.5k and then its all fine drives perfect... now i recently noticed i have two plugs not connected here are the pics....

19897 in this picture it has no where to connect :confused:

19898 and this pic the plug on da motor is cracked so i cant plug it in..



now can someone tell me what these plugs go to and their purpose ??? i would appreciate it

[S-Nation S13]

its you knock sensor plug

[S-Nation S13]

sorry to thread jack but im having the same issue "rough idle" so ive been reading and alot of people say that cleaning the IACV will help, i found the tube that supplies air to it, and what the recommended me to do was spray carb cleaner in that tube while running my car, my question is will this help me out?

IVE already determined that my injectors are working, spark is on point, any advice will do thanks

[Pirate_Freder]

@s-nation s13: I tried spraying carb cleaner into the hose on mine and it didn't help. Ur best bet is to just take it off and take it apart and clean it very thoroughly. It really isn't a very hard job except for putting it back on. I couldn't find a gasket by itself so I had to rtv it and it's a tight spot so u have to make sure to spread the rtv/not use too much and to not bump anything.

[S-Nation S13]

were you able to take off the IACV with intake mani on ?

[Pirate_Freder]

Yep, that's why it was akward. But, like I said, it's really not that bad.

[JJAB305]

Has anyone figured this out yet?! We are having this same issue with my boys 95 S14. Cylinder #3 shows no difference in his car also.

[rioredstang]

I would pull the plugs out and look at them. Is #3 black like too much gas, or white like no gas/lean condition. Do a compression check while you have them out. Any signs of a weak cylinder? Could be a burnt exhaust valve. I have seen bad or broken valve springs cause these problems.

[jdm240sx122]

All your symptoms sound like a bad mas sensor to me, but I would deffinately try cleaning the iacv valve. Also just to let you know My car had a small problem with rough idle and a little hesitstion. So I took off the intake manifold and sprayed a good amount of intake/throttle body cleaner down on and through the throttle body and By doing this I completely solved my problem.

[jdm213]

well if you pulled your plug wire from #3 maybe its the the spark plug, wire, cap, or rotor

[jdm240sx122]

He said he changed his plugs and wires about 8 months ago so I doubt its that.

[nissanfreak317]

He said he changed his plugs and wires about 8 months ago so I doubt its that.

Wires, maybe not. Plugs, definitely though. A spark plug can foul in no time at all, usually due to some other problem but then will continue to cause issues. Much information can be found by checking plugs. It's essential for proper maintenance and problem solving. You really can't rule stuff out based on when it was last replaced, that will just lead to more headaches down the road.

[jdm213]

if i were you i would swich around the plugs take #3 out and put in #1 #2 or #4 in and see if its still #3 is fucking up if not then its your plug fouling out, what kind of plugs you have on?

[dms2]

i was having the same problem,it was a bad injector

[P-Funk alot]

i would say bad injector as well. a bad maf usually would not let you rev above 2500 give or take. could also be a bad plug. but i have been seeing alot of injectors going out on s13 lately.

[emayearecee]

any news with this? i have a very similar problem... rough idle and i disconnected the fuel injectors one by one while the car was running and found which injector was acting up but when i replaced that injector the car wouldnt even start it would crank but never caught and started... then i removed the injector i had just replaced only to get sprayed with gas i dont know what else to do

i also switched spark plugs from a working cylinder to the problematic one and that made no difference
help!

[PeekayzS13]

Did anyone ever fix the issue? My 92 s 13 is having similar issue.

[ceezer]

i had the same issue with me n/a kade. i would remove #2 cable and it wouldn't make a diffidence i also replaced all the damn injectors and same problem... turns out it was a bad o ring and when i replaced that it kept blowing it for some reason. my personal fix to the problem. i doubled up on the o ring closest to the tip.. so remove your injectors one more time and check your o rings and go buy a kit. really cheap at pep boys

let me know if this helps