Random Cylinder Misfire.. Wierd Stuff..

[larryd]

I was driving home from the DSM meet today and I was on it in 3rd gear when all of a sudden the car bucked hard and my CEL came on. pulled over, hooked up my laptop, and retreived the CEL code of Random Cylinder Misfire. I got out and checked everything and it was all fine, nothing appears to have any issues as in loose wires or anything. I giev the car throttle nad UGH.. Its hard to explain but the car sounded like it was only running on 2-3 cylinders. I could definitely tell that the car was misfiring but for no particular reason. I figured Id just drive the car to pep boys and get some new spark plugs as I assumed I must have blown up a plug or something to cause this issue. So I go into Pep Boys, come back out and start the car and sure enough its perfectly fine now. So I cant see it as being the plugs then eve though Im going to change them now anyhow since I have a new set. The only other things are the wires and the coil pack. Is there a way to test your wires to make sure there good or should i just go ahead and replace both the wires and pack?

 

[McGruffAWD]

larry...good god man..where does it stop? i swear you must of the worst luck with your DSM. I really feel for you. I hope nothing else suddenly comes up.

 

[larryd]

yeah tell me about it.

 

[DSMafia]

wires, do the arc test...... coilpack pull it and examine it for any cracks.... i have the same problem, but mine is due to a 1g motor swap in a 2g..... hehe i have the "priveledge" of having to run an ems system to fix it........

 

[GSX4LIFE]

Larry that sounds like the old 1G engine with a 2G ECU problem. The DSM link is supposed to cure all that, but I guess they lost something in the translation.

 

[got traction?]

larryd,, you better get use to it. Only fix is the DSMlink. And anyone on here that say to do the baro mod is just stupid. All that thing does is advance your timing and you will blow up your motor n less then 5 months.

 

[got traction?]

larryd also if you want to run the dsmlink your going to have to get a 95 E-prom ECU. www.dsmlink.com

 

[HighPsi91]

He already has the dsmlink.

 

[larryd]

yes, i already have DSMlink and its still doing this. Im wondering if my issues arent elsewhere.

Could the coil pack be hooked up wrong, I had to rehook it up after replacing it before.

What is the firing order of the spark plugs supposed to be with a 1g in a 2g and DSMlink?

 

[NJGSX96]

You can check the resistance of the wires and coil. To check the coil, you need to pull the wires and unplug the coil. Looking at th coil, it would be like:

|1|2|3|4|
Then with a multimeter, set it to read Ohms. Connect the two prods and test the secondary by putting one prod in 1 and one in 2 and then the same putting one prod in 3 and the other in 4. For the 1G the reading should be 11.5-13.9 I think. 2G is probably the same of close. To check the primary you need to test the plug for the coil attached to the back of he block. It looks like:

|1|2|
-|3|

I think you connect one prod to 3 and the other to 1 and then leave the one on 3 and check it with 2. The reistance is low... like .39-.64 or something like that. If you got a manual, check that out for he tests and numbers you want. If you don't have a manual, let me know. I have mine on the laptop in the arage. I can check for you. Too cold now though to go outside!

Hope I didn't confuse you more. Good luck.

 

[larryd]

Rich,

in all honesty would it be easier to just replace the coil pack?? and is there a difference between coil packs from year to year?? the coil pack I have on my car now is from a 90??

 

[NJGSX96]

Well the resistance test takes maybe 2 minutes. Real easy to do.

As for there being a difference, I have heard there is. I have no first hand experience, but I think there is.

 

[DSMafia]

what codes are you pulling after the misfire? while we're on the subject, does anyone know what the hell a MAF ground error code is?(P1105) I've replaced everything from coils, to wires, to MAS, to the ecu itself and still have the misfire problem....

 

[Tevenor]

Originally posted by larryd
yes, i already have DSMlink and its still doing this. Im wondering if my issues arent elsewhere.

Exactly how is 'still doing this' considering you can tell the ECU to stop checking for Random Misfires ENTIRELY. You did check the DTC list right and uncheck Random Misfire checking?

 

[got traction?]

Do you have your CAS verted or inverted on the dsmlink?

 

[larryd]

i had them all turned off but I reset the battery and didnt think about it and it reset DSMlink to the default options to have all the DTCs enabled. so thats why it showed me the CEL for it but its not even just that.. I could feel it when it happened. The car hit hard, it felt like fuel cut x 1000.. Then the car was misfiring just giving it gas. Have you ever heard a WRX with an exhaust, how it sounds like its missing?? thats what my car sounded like. it went away after I restarted the car but since then it hasnt run right, its just lacking power.

and I have the CAS inverted.

 

[95GST]

You turn it off with DSMLINK

Yes you have to do it yourself, and every time your ECU get reset you have to do this!!

Kind of annoying but sure is better than running on 3 cylinders.

 

[Tevenor]

This shouldn't be a shock to you that you may throw a misfire if you don't turn the Misfire off. This has been a well known issue for a 6-bolt swap into a 2G with the Magnus method since we prototyped it on my engine over a year and a half ago. And if I am not mistaken, this was brought up to you more than once when you decided to scrap your other engine and go with a 6-bolt build up. I personally never threw a RM CEL but others couldn't drive more than a few miles without it popping. Individual cases vary.

My personal belief after having to deal with more of these cases than I can count is that it relates to the RM check code in the OBDI and OBDII code. The OBDII code is a much smaller tolerance for the delay in cycle times than OBDI. Now match that to a 1G CAS that doesn't have anywhere near the accuracy of the 2G equipment and you get an 'out of range' condition which flags the RM codes.

Besides, don't you reload your ECU preset fuel maps and timing maps each time you shut the power down/disconnect the battery? How much harder is it to do the DTC's while you are in there?

I am just not seeing what your issue is.

 

[larryd]

I never said the issue was just seeing the CEL code. I said the issue is how the car is running after it threw the CEL code. It wasnt just a random code, something serious happened because the car bucked HARD.. It nearly threw me out the window. And since then the car has not run right.. Its not a normal problem with the 6 bolt swap.

I think I may have issues with the ignition system. Im going to replace the coil pack, spark plugs, and plug wires and see if that fixes it.

 

[Tevenor]

Originally posted by larryd
I never said the issue was just seeing the CEL code. I said the issue is how the car is running after it threw the CEL code. It wasnt just a random code, something serious happened because the car bucked HARD.. It nearly threw me out the window. And since then the car has not run right.. Its not a normal problem with the 6 bolt swap.

The ECU has 2 different misfire codes. 1 is a cylinder specific code. This will show as 'Misfire in Cyl 1' or 'Misfire in Cyl 2' etc. Then there is the 'Random Misfire' code. Its not a random code. There is a specific code number assigned to a 'Random Misfire' when the ecu can't detect which cylinder is misfiring. It's the fail safe when it knows something is wrong but can't figure out which cylinder is wrong.

I can't diagnose your engine specifically unless I am there. I can only tell you my experience from diagnosing lots of 6-bolt swaps since Marco and I talked about doing it with mine.

 

[germain101]

"It wasnt just a random code, something serious happened because the car bucked HARD."


this doesn't sound like a RM issue to me...i may be wrong but when i would get the RM code, it never made my car do anything violent like you described...the car would feel as if it was running on 3 cylinders, but the RM would come on kind of subtle...and after i reset the computer it would run like a champ again...like i say "i may be wrong", but it doesn't sound like what i have experienced…good luck though, hope you get it all worked out...

 

[larryd]

its prolly just part of my issues. The car has enuf.

 

[TURBOSPYDER]

Originally posted by got traction?
Do you have your CAS verted or inverted on the dsmlink?

anyone know how I can have the CAS Inverted or a procedure similar to it other than sending it to DSMlink to get it done?

Also is it true DSMlink now works on Palm Pilots?

Larry, Im also having the same problem, but I dont have a 1g in a 2g. Have you found the problem yet?

 

[larryd]

not yet.. replacing the ignition system soon.. all the parts are on the way to me..

and yes DSMlink works on palm pilots now as well..

 

[NJGSX96]

What did you get Larry?