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Misfiring problems after turbo install

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3.3K views 18 replies 11 participants last post by  WOR440  
#1 ·
Ok i have done alot of research and reviewed alot of these issues..... I'd say about 5000 miles ago i put on a gt30r kit, PE 850 injectors, pump, Tial BOV with the stiffer Spring, Blow threw maf setup.



Basically the car threw a misfire code.. for a while i was running on a very generic map running rediuclously rich so i got a good map from someone. Now it idles pretty good but tends to bounce around then settle back in... but i get a misfire code all the time.. u can hear it too when it does it, also if u barely throw the throttle down... approx 1-2% throttle. it sputters hard.. and gots 17:1 lean. which also is misfiring due to the fuel problem... but at idle it will settle in perfect sit @ 14.7~1 area.... and then out of no where just start boucing around swinging to full lean to like 11:5-1 and then settles back in.... yet it will idle sometimes for 10 minutes without issues...


also deceleration... if im slowing down and just push the clutch in it will stall alot of times.... i've read people saying plugs cause the problem, which i dropped a step colder set of iridiums in... injectors possibly but they were brand new PE's... didnt want to replace them yet, also i've heard the BOV can cause this... originalyl the BOV would leak open and it would butcher the idle and stall, i installed a stiffer spring but i believe its not opening i will have to monitor it a little more. The car is moded pretty good

Its a 2006 car but i doubt the warrenty will be good with a gt30r and computer and what not


Mark
 
#5 ·
no clark did a car with the same setup @ my location the week before i got my car done, he sent me that map... my car made 380whp @ 21psi on pump... so its protuned well... the misfiring is a common problem i found on this site and the check engine light and crap comes on and stays on and the cruise flashes.. its really just annoying.
 
#6 ·
Djreversal said:
no clark did a car with the same setup @ my location the week before i got my car done, he sent me that map... my car made 380whp @ 21psi on pump... so its protuned well... the misfiring is a common problem i found on this site and the check engine light and crap comes on and stays on and the cruise flashes.. its really just annoying.
:naughty:
 
#7 ·
You have got some serious problems if your throwing misfire codes. Every car is different and someone sending you a map even if it is a certified tuner should not be sending you a map that was tuned for someone else's car. You should only be running that map for max the drive to a dyno/road tune. Do your self a favor and don't drive the car until it is tuned with a tuner in car. There could be a variety of things wrong including but not limited to tip-in, fuel trims, timing, knock thresholds, avcs, and etc.
 
#8 ·
That doesnt sound like a good idea running a tune made for another car.. Not all mods/cars are the same, and every car runs a little bit different.. I highly doubt the car that that map was made for had the exact same mods you had, and even if it did all cars are differnt, and running one map on one car doesnt always work the same on another car.. I'm surprised Clark would send you a map on this type of setup and not tell you it's just to get you to the tune and not go into boost, basically a base map until you can get your car protuned.. Hopefully he can chime in and clear this up, but you need to get your car tuned for YOUR setup.
 
#9 ·
STimo said:
That doesnt sound like a good idea running a tune made for another car.. Not all mods/cars are the same, and every car runs a little bit different.. I highly doubt the car that that map was made for had the exact same mods you had, and even if it did all cars are differnt, and running one map on one car doesnt always work the same on another car.. I'm surprised Clark would send you a map on this type of setup and not tell you it's just to get you to the tune and not go into boost, basically a base map until you can get your car protuned.. Hopefully he can chime in and clear this up, but you need to get your car tuned for YOUR setup.
no he still recommended i get it tuned but when i dyno'd the car and it made the power it did, had 0 knock and safe AFR ... i wasnt worried about squeezing any more power out of it. but this check engine some people said they get it also and just ignore it... cause the car does no misfire except at an idle, and if you do a search on these forums for misfire code u will get like 50 hits of peoples cars doing it from stock to fully mod'd... i guess ill just have to start ripping **** apart, or set the car on fire and buy and evo.. those are my 2 choices now... just trying to finish my supra before i throw this car in the garbage
 
#10 ·
Well sht, if you have a supra that you're building why are you even wasting your time and money on this car??
 
#12 ·
Phil said:
so your saying.. you got maps off other people.. but havent got your car protuned specificaly for your car?
Problem solved right there.......
:tdown:
 
#13 ·
2fas4u said:
Problem solved right there.......
:tdown:
somethings mechanically causing the problem.. its not the tune.... AFR is perfect @ idle, threw redline... im not getting and idle hunting at all. the plugs are misfiring randomly, or the injectors are a problem, or the BOV may be opening i guess ill just have to play around with it... yesterday it just sat and idled perfect for bout 20 minutes while warming up... never having the misfiring... then i drove it around a bit, and it started doing it.
 
#14 ·
A bad injector will likely be your problem. You saying that it only happen at idle gives it away. The two Subaru dealers that I deal with regularly replace injectors all of the time. Each car has you same problem. And most of them are stock or close to it. Pull the code, see which cylinder is misfiring, and you will know which injector to have checked/replaced.
With that being said, you STILL NEED TO HAVE A TUNE CUSTOM FOR YOUR CAR.
 
owns 2019 Subaru WRX STI Base FP Green Flex Fuel
#15 ·
JDM-STI said:
A bad injector will likely be your problem. You saying that it only happen at idle gives it away. The two Subaru dealers that I deal with regularly replace injectors all of the time. Each car has you same problem. And most of them are stock or close to it. Pull the code, see which cylinder is misfiring, and you will know which injector to have checked/replaced.
With that being said, you STILL NEED TO HAVE A TUNE CUSTOM FOR YOUR CAR.
ill have to run it again i wanna say it was 2 / 4 misfiring.... and they are PE850 injectors. Im also going to check plug gap to
 
#16 ·
I have been having misfires with a Subaru proprietary misfire CEL (?????) since being protuned by Clark Turner. I also have PE850s, FP 3"TD06H-20G, and all supporting mods. I put my stock injectors back in a couple weeks ago and loaded the Cobb economy map to see if the problem would go away. The results were inconclusive because I have TGV deletes and still got CELs. Basically, my setup is such that this troubleshooting method was a waste of time and effort.
Since I put the PE850s back in, the rough idle has changed. I obviously have at least two bad injectors. I put the injectors back in random order and now on whole side of the engine is misfiring instead of, say, one cylinder from each side and yes, I still have misfire CELs. I am scheduled for a tune after the first of the year and the tuner says he can tune the injectors out. We shall see. I know that Clark insisted it was nothing to do with the tune and he was no help whatsoever.

CB
 
#17 ·
fastcb said:
I have been having misfires with a Subaru proprietary misfire CEL (?????) since being protuned by Clark Turner. I also have PE850s, FP 3"TD06H-20G, and all supporting mods. I put my stock injectors back in a couple weeks ago and loaded the Cobb economy map to see if the problem would go away. The results were inconclusive because I have TGV deletes and still got CELs. Basically, my setup is such that this troubleshooting method was a waste of time and effort.
Since I put the PE850s back in, the rough idle has changed. I obviously have at least two bad injectors. I put the injectors back in random order and now on whole side of the engine is misfiring instead of, say, one cylinder from each side and yes, I still have misfire CELs. I am scheduled for a tune after the first of the year and the tuner says he can tune the injectors out. We shall see. I know that Clark insisted it was nothing to do with the tune and he was no help whatsoever.

CB
well definitely keep me informed if your new tuner can fix that issue...... im wondering maybe if its like the injector timing that was changed or what not. ill have to see... but its only in the 1000rpm and lower area that this occurs.... drivability is perfect except deceleration... if i just clutch it in from say like 3k or higher, it will usually stall which is annoying..
 
#18 ·
Djreversal said:
well definitely keep me informed if your new tuner can fix that issue...... im wondering maybe if its like the injector timing that was changed or what not. ill have to see... but its only in the 1000rpm and lower area that this occurs.... drivability is perfect except deceleration... if i just clutch it in from say like 3k or higher, it will usually stall which is annoying..
Yours could possibly be spark plug gapping. If you have a bad injector, your tuner can't tune that out...
 
owns 2019 Subaru WRX STI Base FP Green Flex Fuel