Running on 3 cylinders

[(Yoshi)]

Hey, my motor has been doing good but then one day after school it started running really rough. So I checked the plugs and all that and ended up replacing the cap rotor and plugs, the wires were fine, and that didn't help so I did a cylinder drop test where you unplug one wire at a time to see which cylinder is the weak one. So I unplug the first and the engine didn't idle any different and when I unplugged the other three the engine bogs down. So I switched the #1 and #2 wires and the same thing happened. Tomorrow Im going to see if I get any compression (old school, hand over the plug hole, cuz I don't have a compression tester) then if that doesn't work Im going to check the fuel injector. I may try that STP fuel treatment that is supposed to clean your injectors. I don't know what could cause this, Im just trouble shooting right now. Any help would be great thanks...

Adios Josh

[tonynalli]

not really sure that an injector would just stop working.and if it did i dont think injector cleaner would do anything.. i would recoment mabey checking the injector wires/ plugs. its actually kinda tuff to determine if they have gone bad because you wold have to stip the wires and that would **** them up more.i would recomend getting differnet one from the sealership.

[240DRFT]

just go buy a compression tester, u can get one for like 20 bucks...the hand way just doenst seem to accurate. cross your fingers its not the piston rings.

[(Yoshi)]

Yeah Im going to get a compresion tester from my neighboor tonight and will test it either tonight or tommorow. I think it is my rings tho cuz it was smoking a little prior to this and I fired it up today and it smoke quite abit.

AdiosJosh

[s14 2510's]

Is the plug in the cylinder wet with gas. I have replaced multiple injectors in ka's that is more than likely your problem. I could see you spinning a rod bearing before you lose compression. I have a set of used injectors that all worked good when I pulled them off a ka that spun a bearing. It wouldn't hurt to do a compression test also. Take a voltage tester and check the ohm on all the injectors to see if they test out fine then you can tell if you have a bad injector.Could be bad valve stem seals thats why it smokes on start up.

Modified by s14 2510's at 4:29 PM 10/25/2005
Modified by s14 2510's at 4:31 PM 10/25/2005

[s14_drifter8]

I bet it's a dead injector. I had the same problem. One day after some hard acceleration the engine suddenly sounded like a WRX. Took me a month to figure out that it was a bad injector. Or it could be a piston ring. Just better hope it's not a piston ring. Good luck!

[(Yoshi)]

Yeah I unplugged the wire to the injector and it did nothing but the others bogged the engine down, so IM going to check it.

[vvaffle]

I had the same problem. Turned out to be my injector. What you can do to check this is swap the injector from the bad cylinder to another cylinder. If the problem moves, the injector is your problem. This way, you can also check if the injector o-rings are bad. Careful though, swaping the injectors too many times will take a toll on your o-rings, but they are cheap from the dealer, less then $5. Let me know if you need help figuring out how to take out the injectors, make sure not to strip the screws holding them in.

[s14 2510's]

I had the same problem. Turned out to be my injector. What you can do to check this is swap the injector from the bad cylinder to another cylinder. If the problem moves, the injector is your problem. This way, you can also check if the injector o-rings are bad. Careful though, swaping the injectors too many times will take a toll on your o-rings, but they are cheap from the dealer, less then $5. Let me know if you need help figuring out how to take out the injectors, make sure not to strip the screws holding them in.

Not if you use vasaleen to lube the orings when u slide them back in. I have never had to replace orings on a car if you take proper care when reinstalling them. I have taken numerios injectors in and out of cars and never had problems. Its not like they are moving around and ware away or anything. But they can dryrot from age but you will be able to tell that when you take them out.

[vvaffle]

Well there you go, I learned something new as well.

[(Yoshi)]

@vvaffle LOL funny you should say that about stripping the screws.... well I tried checking the injectors a while ago but majorly stripped one of the screws and even tried special bits and easy outs. None of that worked but made it worse. So I got some liquid wrench and sprayed it on and let it set overnight then before I tried to get it out today after school I sprayed more on and then put the small sharp flat head on the top edge of the screw and hit it acouple times to leave a groove then I just angled it and tapped it around and the screw came right out, then I replaced it.

Any way after I got the cap off I tried to get the injector out and it wouldn't come out so I searched and found if you soak them in wd-40 it helps, is this true, if not how do you get those suckers out.

@S14 thanks for the tip

adiosJosh

[hudy]

I wouldn't do the fuel addative cleaner. Put a long screwdriver on the injector housing and listen on handle end of the screwdriver. It should be clicking at a regular rate. Listen to the other 4 injectors and compare the sound. Also you could do a resistance check on the injectors. They should all have a similar value.

[(Yoshi)]

Yeah the fuel addative wouldn't hurt but I have done the screw driver thing already and they all tick pritty much the same except the first is a little bit quieter. Instead of doing the resistance check Ill just swap the #1 and #2 injectors and see if the problem moves from the first cylinder to the seccond and if it does then Ill replace the injector if not Ill do a compression test and see if I need rings or valve is stuck or what ever. Hopefully its my injector...

AdiosJosh

[vvaffle]

Both methods that hudy said should work. The problem with listening on the screwdrive is that if you have any other ticking (like timing chain hitting the guides) it will be hard to distinguish noises. I did this and it seemed like every injector was ticking, but I knew that the #1 didn't work.

Using the resistance to check would work great if the injector is totaly broken. If it's just dirty the resistance might show up fine. A good injector has resistance somewhere in the teens. Anything outside of that, it's most likely not fixable without some serious work (not worth it, can get a stock injector for cheaper).

As far as getting the injectors out, I wish I had a picture. structure240sx showed me this trick. Get two flathead screwdrivers; one may be enough. Now, you see the part of the injector where the wire plugs into. Stick the thicher flathead under that and against the metal rim of the hole that is right bellow it. Now instead of moving the flathead up and down, rotate it in place so only one side of the tip goes up at a time and the other side is pushing at the part bellow it. Do this for a while, you might be able to get it out just like that. If not, while you are doing this, some space around the injector will show up. Stick the other flathead in there and pry it out.

If this doesn't make sense, let me know and I'll take a picture.

PS. I knoew you responded before I finished writing this but it took a while to write and I refuse to delete it.

[(Yoshi)]

Ok ill try that screw driver thing...

[hudy]

They are usually loud enough to hear even with other engine noises. Unless you chain is severly loud. In which case you probably should give that attention first. The swap the injector idea is a good one. Let us know how it goes.

[(Yoshi)]

Yeah I could hear them tick over the other noises.

Any how I swapped the #1 and #2 injectors and sure enough the problem moved w/ the injector. So I went to Murrays and I placed an order for an injector and am going to go pick it up tommorow after school.

Man those things don't want to come out or go back it. I tried the screw driver twist idea and that helped a little but didn't get it ou so I ended up taking the plastic wire covering off and turned the injector so the plug was facing the valve cover and got the biggest screw driver I had and used the valve cover for leverage and sent the injector flying lol then to get it in I just used a small hammer and an extention for the ratchet and tapped them in.

At least the fuel injector will get it running like normal, Ill worry about it smoking later. Ill probalby do a rebuild down the road when I have time and money to do so.

After I get the injector Im going to run a compression test. Ill let you know how everything turns out.

It will be my first compresion test so if you could make sure I have the steps right and let me know what the last steps are that would be great.1.warm up engine2.pull all the spark plugs3. unplug the fuel injectors4.screw in the tester5.then do I crank the engine? Not sure what to do after this

Thanks for all your help guys I realy appreciate it.AdiosJosh

[vvaffle]

Just wondering, but how much did you pay for a new injector? Also get an upper and lower injector o-ring from the dealer if they don't come with the injector. You are definetly not supposed to reuse the old ones.

As far as the compresion test is concerned, I am not sure but it is explained in the factory service manual and you can download that here http://www.zeroyon.com/index/content/view/24/47

[(Yoshi)]

I gues they had two injectors for the 91 and one was $92 and the other was $116.99 and I wasn't sure wich one to get so I let the guy at Murrays look at it and he ordered the $92 on but it was the wrong one so I am going to take it back and exchange it for the $116 one.

Ill check mine I got an fsm.

Off I go to exchange injectors.

AdiosJosh

[vvaffle]

I don't mean to say that you made the wrong decision, and a new injector might be nice, but you could have gotten a set of 4 used working ones for half that much.

[(Yoshi)]

from nico? ok so I wait until I find someone willing to sell a set of them and then wait for them to send them and have them back out at the last moment. Thats ok. I need the car for school I don't have time to wait on some one.

[s14 2510's]

I would have sold you good used ones for like $15 a piece. They were running on my s13 a month ago.

[(Yoshi)]

thanks I apreciate it. Just to late =(