Real bad misfire, PLEASE HELP PLEASE

[JayRolla]

I cant figure this out at all. When I first got my car it would start to misfire sometimes real bad, like only 2 pistons are firing. The cel would also pop up. If I reved the motor a little it would go away. Everyonce in a while it would come back but always go away.

Now it does it all the time. The cel is an ignition coil code. I replaced the wires, plugs, swapped the coil, transistor, and swapped in a different working ECU. Nothing worked. The car idles fine, but is only running 2 pistons. What would cause this other than what Ive fixed. Do you think the CAS may be the problem. PLEASE I NEED HELP

 

[talontsi18]

I suggest sticking a timing light on the car, just to see if everything is set up where it needs to be. As far as the CAS I have no clue. My car has a slight mis to it and I haven't figured it out yet, but it not even close to what your car is doing. Good luck man!

 

[JayRolla]

Yea it sucks, dont know what to do. Will someone please help me. there has to be something im missing. Timing is good.

 

[staticbrainwash]

See if you can make up a cheap noid light. Or better yet, with the car running pull injector clips one at a time. If all your ignition is good, and you've checked timing, and (i hope you've checked compression) that good too, then i'd lean toward injectors.

Which were my problem when i first got my car too. Changed them out with good working cleaned injectors and i was all good.

Or change around your injectors to see if the problems move with the injectors.

 

[miden]

Yea it sucks, dont know what to do. Will someone please help me. there has to be something im missing. Timing is good.

Do you have a SAFC or some other tuning device? I've seen SAFC wiring come loose & short things out at the ECU and cause misfiring on two cylinders.

Of course this was after swapping out coil packs, balast resistors, just about the entire ignition system...

-M

 

[JayRolla]

The motor was just rebuilt and compression was fine last I checked. I will check to see if its the injectors. So if it was an injector that means if I pull the wires they all should be firing right? That would mean it is a bad injector right? I have no tuning devices hooked up at all. I will check the injectors tonight.

 

[staticbrainwash]

Yeah, as in, check one. If it does nothing that = your bad cyl. If it changes the way the car runs (which at this point would probably stall the car) then you know it's good. Plug it back in, rinse and repeat.

It's a real easy way to power balance test. I would also try to move them around a bit and see if the problem is cyl based, or injector based.

It sounds A LOT like my problem when i got my car. But you never know. . . it IS a DSM, haha.

 

[miden]

The motor was just rebuilt and compression was fine last I checked. I will check to see if its the injectors. So if it was an injector that means if I pull the wires they all should be firing right? That would mean it is a bad injector right? I have no tuning devices hooked up at all. I will check the injectors tonight.

Do you know which cylinders are not firing? The fact that two are out suggests that one coil is not getting the signal to fire.

-M

 

[donmagicjuan]

Jason,

I wouldn't think you'd be getting a CEL for the coils if you had faulty injectors. It's possible you have a continuity problem between the ECU and the power transistor if you've replaced all of the possible components already. Here's a thread regarding a similar problem with cylinders 2 & 3: http://www.dsmtuners.com/forums/showthread.php?p=150995644#post150995644

Obviously, if your problem is with 1 & 4, you'd have to check continuity from the other pin number.

Hope that helps.

EDIT: miden has the same idea as me. I was assuming you were getting a coil CEL code, but now I see you didn't mention what it was. That would obviously be helpful.

 

[staticbrainwash]

I was getting all sorts of weird stuff when my injectors went. So thats why i brought it up. Also, it's a DSM, i wouldn't put it past it.

But really, it was just another thing to test to make sure ISN'T the problem. Because you can't be to careful.

 

[donmagicjuan]

Don't worry, I wasn't knocking your advice. It wasn't till after I posted my response that I realized he didn't specify the CEL code. Without knowing that, it certainly would be a good idea to check the injectors.

 

[blcknspo0ln]

1,000+ posts and you still don't know that you can't cross post?

Just to add to my other post, If you're getting an ignition coil CEL, have you checked the actual PLUG that goes to the coils? Have you checked continuity between the coils? 4-1 and 2-3 should have ~13k ohms. Pull out each spark plug wire (one by one) and attach a new spark plug to the wire boot when you unplug it and check if there is spark. Do this to verify which cylinders are getting spark. If it happens to be 4-1 or 2-3, then you can then narrow down your diagnosis.

 

[JayRolla]

Thanks guys I am thoughing a coil code, so dont think its injectors. I need to figure exactly what cylinders are not firing. Thanks for the replys I will follow up.

 

[brute]

\If you're getting an ignition coil CEL, have you checked the actual PLUG that goes to the coils?

Hey, that's what I said copy cat!

 

[JayRolla]

What would I check. I noticed when I swapped the coil that the plug had some oil inside of it, dont know how. Also when I looked inside the coil where the wires plugged into I could see that two where a copper dirty color and the other two where shinny clean. Dont remember which cylinders they where, but would the dirty one mean they are not firing? Also wouldnt this eliminate any component after the coil?

 

[staticbrainwash]

You said plugs and wires are new right? What kind did you buy?

 

[brute]

JayRolla, what I mean by that is track the plug wire to make sure you have the right cylinder plugged in to the right coil.

 

[JayRolla]

Oh yea the wires are correct. It started misfiring one day on its own. Just to make sure can someone post the correct way the wires plug to the coil. I put new plugs in and swapped my brothers MSD wires on just to check if it was that.

 

[brute]

Pull the wires out of the spark plug wells and look for little holes. They'll be tiny so look closely. Look up and down the shaft. Also check the 90* bend where the shaft meets the wire and look for condensation. You can also look for oil around the base of the spark plug well.

 

[JayRolla]

Thanks for all the help guys. Still cant figure it out. Im bringing it to my mechanic the DSM Guru we call him here and see if he can fix it. He has like 5 trannys that where shipped in so he is going to be busy, hope he finds time to fix my POS

 

[JayRolla]

Well before I brought it to the mechanic I decided to get ballzy and pull the wires one at a time to see if they where firing. They all WORKED. So I started thinking it has to be a fuel problem. I pulled the plugs off the injectors and #2 seems not to fire but does have spark. I borrowed my mechanics stethoscope and listened to each injector and #2 sounds way quieter than the rest meaning its burned up, I hope.

Now would a bad injector cause me to through a ingnition coil code??

 

[miden]

Now would a bad injector cause me to through a ingnition coil code??

It would seem so.

If I were you, I would measure the injector impedance for all of the injectors. That would tell you if that one was burned out and if you had any others on their way. (I think the ohm readings are in a tech article on here or in the vfaq...) Then you could move that injector to a different cylinder for a 100% confirmation.

So. Ready to upgrade your injectors?



-M

 

[JayRolla]

Yea my mechanic sold me a set for 10 bucks each. Im going to through those in. I have 550's just nothing to control them.

 

[staticbrainwash]

Hah, and you all thought i was crazy when i said check injectors.

*does a dance* I wouldn't have mentioned it if i didn't think it was plausable. Jerkfaces!! (Just playing around)

I hope that fixes things for you bud, if so, you can pick up injectors pretty cheap. Or hell, they might just need to hav a professional cleaning.

 

[JayRolla]

Yea thanks man, I didnt think it was the fuel system because of the ignition code. But my mechanic said it could through that if the cylinder is not firing. He said its real wierd for the small 450 mitsubishi injector to die like this. He said its been a long time since hes seen it. Rep points for all!!!!!!!