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MISS fire ..HELP PLEASE

33K views 58 replies 18 participants last post by  AllExtinct 
#1 · (Edited)
EDIT : go to last page for the lastest info :)

What NOT to put on your
2006 wrx TR
MOD LIST:

TBE
Big 16g
MBC
Apexi SAFC........................Just took it off
HKS fuel cut defensor..........Just took it off
Grounding mod
FMIC w/ CAI
BOV


OK this is what happened....

All of these mods have been installed for a few months WITH no problems at all

and all of a sudden last week it started to run like crap when takeing off from a dead stop would studder and barly move....BUT if i reved the motor first and kept a higher steady RPM it would take off FINE ......THEN it seemed like if I TURNED OFF the AC that it would work good........

THEn it started to get worse...even with the AC off it still studdered ....and now no matter what i do IT does it all the time ...I can get it to higher rpms when moveing and it gets a LITTLE better but sounds/ feels like it may only be running on 3 cyl's

AND the whole time I hae been throwing a ( MISS FIRE CODE) P 304
I reset the ECU and it doesnt REALLY seem to help.. the CEL will come back on in a few miles.....but it doesnt come RIGHT back on....

I was thinking it might be a fouled plug ### i have it tuned RICH at high rpms/boost and the BOV makes it run REALL rich in between Shifts.......


I have read on here and seems like people have been haveing problems with the SAFC ( is that right away or did it take a while to happen ????)



ANYWAYS please help out guys ...thats alot!!!!!

EDIT :

i pulled 2 of the spark plugs ( the easy ones on the pass. side).
and thay both look the same ...thay look fine ..good really ..THEY ARE red or orange ( thats good right? )
?????????????
it looks like thay would spark fine!

so now I am scared!!!!!!!!

AND the CEL code is P304....I am not sure about the 2006 wrx ..but i think thats the #4 cyl .....RIGHT???? and if so ..is the #4 in the back on the Driver side?




ALSO ....Does anyone know what the WHITE wire on the Throtle bodydoes ( where the big clip plugs in on the throttle body) .. its right next to the Turbo ....### when I put mu FMIC pipe on it rubed up again it and cut into it ..and was ( KINNA ) shorting out ...but it dodnt mak any difference...I didnt notice for a week or so when I took the pipe off . and then I fixed it so it wasnt touching anything any more...... WHAT DOES THE WIRE CONTROLL.....i AM HOPEING THAT I DIDNT MESS MY ECU UP WITH THAT ( i doubt i did ..but ..I am still scared )
 
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#28 ·
Yes I know its a cyl 4 misfire :) and nothing i have done has changed it swaping plugs/coil packs/ injectors all still # 4

AND I have done a Compression check ...All 4 cylenders are Perfect!!!


AND i just went and looked and

DRIVER side = NOT plugged in

Passenger side = Plugged in..


i donno whats wrong .....I mean this car BUCKS BAD sometimes ...and others it just misses and hesatiates
 
#30 ·
haha...did i confuse you ...Or are my problems confuseing you ..hehe :) ??????????

and yah i guess i am gonna have to take it to the Stealership ...but thats gonna have to wait untill after tuesday... tuesday my buddy at a shop is taking my 16g turbo off and installing my STOCK turbo.. ( the 16g is Blowing alot of oil anyways..gotta fix the seal )...

SO i have untill then to TRY to fix it.............................. :) ... I already went in there once with my FMIC on and my BOV and MBC and thay wouldnt cover it under warrenty ....and the guy told me to take all the stuff off and thay would do it under warrenty .....SO i hope he was not just blowing smoke up my asss...### he already informed Subrau of my mods ......SO ..I wonder even with ALLLLL of the mods OFF ...will it be under warrenty ?????????
 
#33 ·
I just spent the morning driveing around stareing at the Boost gauge ...it SEEMS that the car starts to have problems ( miss) when the car starts to boost?????....what would this mean ....would a bad turbo blowing oil do this????......DOes ANYONE know what the sensor at the throttle body ( where i shorted the wire) does?? is it a TPS or some sort of boost sensor......i thin ki read in some COBB AP manual that the boost sensor is after the TB ????..?? ?????????
 
#34 ·
OMG.....well PROBLEM has been found . :(

I dont know how I over looked it or ...how I ...oh hell... I just dont know....

BUT 5k miles and 50 pounds of Compression in cyl #4 .
..

How do I find out if its a ring, valve or piston ???

and how much am I looking at to have it fixed.( depending on each of the above). ???
 
#35 ·
brokenarrow said:
OMG.....well PROBLEM has been found . :(

I dont know how I over looked it or ...how I ...oh hell... I just dont know....

BUT 5k miles and 50 pounds of Compression in cyl #4 .
..

How do I find out if its a ring, valve or piston ???

and how much am I looking at to have it fixed.( depending on each of the above). ???
You need to do a leak down test to figure out if it's a piston or a ring. I forget what means what with a leak down test because I haven't done one in forever, but someone else can hopefully chime in here. Personally, I'd get that car back to stock and hope that the dealer doesn't know you've done all sorts of stuff to the car and take it in to have it looked at. If not you're looking to pull that and fix the piston or the ring. Good luck.
 
#36 ·
Seriously somebody needs to make this a sticky to show what happens when you put all the "bad" stuff on and the end results.Just because the you car is running doesn't mean everything is OK.There is so much info all over the net about using those parts and what happens and you used them ALL together?Try sending in an oil sample to Blackstone labs and they will give you an idea what happened by the metals found in the oil.The test runs about $25.I betting on piston or valve here.
 
#37 ·
You are correct.!
They should make this a STICKY .
TO tell the truth I have never been able to find a thread about a SAFC2. I have seen a few saying nothing of importance.
I hve looked on here and on a few other sites..
I should have asked before I started to modd.

SO if this was made a sticky it might help some person like me .
I would have loved to come acrossed this thread when I was putting all the crap on my car .:)
 
#38 ·
brokenarrow said:
You are correct.!
They should make this a STICKY .
TO tell the truth I have never been able to find a thread about a SAFC2. I have seen a few saying nothing of importance.
I hve looked on here and on a few other sites..
I should have asked before I started to modd.

SO if this was made a sticky it might help some person like me .
I would have loved to come acrossed this thread when I was putting all the crap on my car .:)
I'd just like to tell you what I think happened to your car...

The SAFC is capable of controlling a/f points. It does this using static numbers at various RPM ranges. It basically overrides what the ECU wants to do. It is a problem with piggy back systems in general. I'm willing to bet that during a spirited drive the engine was running a little too lean and was either not able to pull enough timing, or it was not pulling timing at all. As a result you had a bunch of detonation and fried the ring on Cyl #4. I'm actually suprised it didn't happen to #3 first as that usually runs the hottest on these cars but I guess all it takes is a big enough kaboom to make it go.

I am going to guess that you just need a new set of rings and it will be fine, but the fact remains that the motor has to come out of the car. Have you started taking it back to stock yet?
 
#40 ·
JiveMasterT said:
I'd just like to tell you what I think happened to your car...

The SAFC is capable of controlling a/f points. It does this using static numbers at various RPM ranges. It basically overrides what the ECU wants to do. It is a problem with piggy back systems in general. I'm willing to bet that during a spirited drive the engine was running a little too lean and was either not able to pull enough timing, or it was not pulling timing at all. As a result you had a bunch of detonation and fried the ring on Cyl #4. I'm actually suprised it didn't happen to #3 first as that usually runs the hottest on these cars but I guess all it takes is a big enough kaboom to make it go.

I am going to guess that you just need a new set of rings and it will be fine, but the fact remains that the motor has to come out of the car. Have you started taking it back to stock yet?
yes the only thing on the car is EXHAUST and cobb AP


I do have a question. :
Would 2006 wrx heads bolt on a 06 sti block?
thay are both 2.5
I am pritty sure that thay will. but i need to know for sure :)
 
#41 ·
brokenarrow said:
yes the only thing on the car is EXHAUST and cobb AP


I do have a question. :
Would 2006 wrx heads bolt on a 06 sti block?
thay are both 2.5
I am pritty sure that thay will. but i need to know for sure :)
Since the misfire issue's pretty much addressed, can you start a different thread for this new question.

I don't want this thread to go in a million directions. Since it's a sticky, I'd like it to stay relevent and on-topic.

Thanks. !Thumbs Up
 
#42 ·
JiveMasterT said:
I'd just like to tell you what I think happened to your car...

The SAFC is capable of controlling a/f points. It does this using static numbers at various RPM ranges. It basically overrides what the ECU wants to do. It is a problem with piggy back systems in general. I'm willing to bet that during a spirited drive the engine was running a little too lean and was either not able to pull enough timing, or it was not pulling timing at all. As a result you had a bunch of detonation and fried the ring on Cyl #4. I'm actually suprised it didn't happen to #3 first as that usually runs the hottest on these cars but I guess all it takes is a big enough kaboom to make it go.

I am going to guess that you just need a new set of rings and it will be fine, but the fact remains that the motor has to come out of the car. Have you started taking it back to stock yet?
The main problem with the SAFC is it's all fuel based on TPS position and RPM,not boost or load.And it has absolutly no control over timing.So you have a piggy back that used two sensors to decide fueling while the stock ECU uses around 12.I know the DSM guys used to use a "hack" method by connecting the TPS signal wire to an airflow sensor so fueling would be some what relative to boost.Plus the MBC,intercooler and intake were not helping things.
 
#44 ·
Im suprised no body posted this yet but more then half the time there is a check engine light for a cylinder 4 missfire is caused from the valves running too tight. This is not as serious as it sounds because its only shims and buckets, about a 3-5 hour job. We get the same problem a lot in our shop and a valve adjustment always fixes the problem. I have the same problem with my car but you know its bad when you come to a stop and the car stalls until then either put up with the light or go get it fixed! hope that helps some people out there.
 
#45 ·
Also lightned crank pulley or lightned flywheel can cause phantom missfires on all 4 cyclinders.With custom tuning you can go back and change the parameters the ECU uses to decide when to trigger a CEL.Its set at the factory for" 1 missfire" triggers a CEL.I have adjusted mine to "3 missfires" triggers a CEL as my ACT Streetlight flywheel will sometimes trigger numorous random missfires every now and then.Sometimes days apart,sometimes months apart.
 
#51 ·
i have a 03 wrx, stage 2 tune with cobb ap and full turboback setup. i started getting misfires with cyl 3 after week of owning it, so i changed 2 coils, then continued to get them sometimes other clys then 3, so i changed the other 2 coils, misfires continued so i changed the plugs, im still getting missfires on all cylinders, theyve gotten worse over time, the car has 119,xxx miles, it doesnt run rough at all, never felt a misfire it happens at any rpm.. any suggestions
 
#53 ·
misfires continued so i changed the plugs
I think so Randy


1-Did you use the correct plugs? I'm not saying the same plugs that were in there. I mean the correct plugs from the manual.
2-What did you gap them to? If you did get the correct plugs from the manual, do a compression test.
3-What did the old plugs look like?

I'd say to SeaFoam the car to see if that helps buuuuuut.
 
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