Welcome to the North American Subaru Impreza Owners Club Monday September 1, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Service & Maintenance

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 04-18-2008, 08:50 AM   #1
sujorosa
Scooby Newbie
 
Member#: 146739
Join Date: Apr 2007
Chapter/Region: NESIC
Location: Connecticut
Vehicle:
1999 Camaro z28
Red

Question Misfire around 3000RPM???

Hey everyone,

I have run into some trouble recently and can't figure out the root cause as of yet. Here is the rundown of what is happening:

When i am driving normally, in any gear around 3000 RPM my car is stumbling. In some cases so much that I get a misfire CEL in cylinders 1 and 3. The stumbling only lasts between 2900RPM to about 3200RPM. Partial throttle I feel it big time, and in WOT I still get the stumble as well I recently noticed - but it's no where near as noticable. The car feels solid otherwise. Even cruising on the highway at about 70-75mph when my car is around 3000RPM you can hear it stumble - temporarily throwing a CEL without the cruise flashing.

My current mod list is:

Buschur Racing 3inch Turbo Back Exhaust
Custom 4-1 header and uppipe
Agency Power 3inch Turbo inlet
Perrin Big MAF
Blouch Dominator 3.0R (GT3076)
SSAutoChrome FMIC
Power Enterprises 850cc Injectors
Agency Power Fuel Rail
Agency Power TGV Spacers
Grimmspeed TGV Deletes w/ Heat Coating
Walbro 255 Fuel Pump
Forge BPV
Summit Racing Heat Wrap
GM Boost Solenoid
NGK Iridium 1 Step Colder Spark Plugs

I just ordered new 1 step colder plugs thinking maybe the gaps were off, or since at one point I found my car to be running extremely rich that it could have fouled something. I am putting those in this afternoon. I was told it may be failing coilpacks as well. Any help would be greatly appreciated.

Thanks,

Matt
* Registered users of the site do not see these ads.
sujorosa is offline   Reply With Quote
Old 04-18-2008, 02:24 PM   #2
sujorosa
Scooby Newbie
 
Member#: 146739
Join Date: Apr 2007
Chapter/Region: NESIC
Location: Connecticut
Vehicle:
1999 Camaro z28
Red

Default

bump, any ideas ppl? all help would be greatly appreciated!
sujorosa is offline   Reply With Quote
Old 04-19-2008, 09:05 PM   #3
awdguy
Scooby Newbie
 
Member#: 59101
Join Date: Apr 2004
Location: michigan
Vehicle:
2004 wrx
white

Default

maybe your coil packs. spray a little water on the coil packs and see if it acts up. or just swap the coils that are misfiring with ones that are not, see if the misfire jumps. if it does, then you need new coil packs.
awdguy is offline   Reply With Quote
Old 04-20-2008, 04:27 PM   #4
sujorosa
Scooby Newbie
 
Member#: 146739
Join Date: Apr 2007
Chapter/Region: NESIC
Location: Connecticut
Vehicle:
1999 Camaro z28
Red

Default

spray water on the coil packs? any more info on this? never heard of doin that b4 thx
sujorosa is offline   Reply With Quote
Old 04-20-2008, 04:41 PM   #5
stiplayer
Scooby Specialist
 
Member#: 173727
Join Date: Mar 2008
Chapter/Region: RMIC
Location: Cottonwood Heights
Vehicle:
2004 Sti Stage II

Default

hmm thats pretty weird i see that **** on fords all the time hahahaha but never ona sub
stiplayer is offline   Reply With Quote
Old 04-20-2008, 05:04 PM   #6
stretchedk7
Scooby Guru
 
Member#: 170602
Join Date: Jan 2008
Location: j-ville fl
Vehicle:
06 Wrx RWD Auto
76MM-AEM-2200's

Default

Coilpack probably....how does the big maf work for you? I had one for a while but never could get it to fit that great with my front mount and the silicone coupler leaves much to be desired..Also if in your ecu map there is a rich point or two that could cause a very slight hestitation or bog feeling. Let us know when you get it fixed..
stretchedk7 is offline   Reply With Quote
Old 04-21-2008, 09:31 AM   #7
sujorosa
Scooby Newbie
 
Member#: 146739
Join Date: Apr 2007
Chapter/Region: NESIC
Location: Connecticut
Vehicle:
1999 Camaro z28
Red

Default

i replaced the coil pack on cylinder 3 and moved the others to see if anything would change its location, it didn't change anything. it still shows Cylinder 3 misfire. new spark plugs are in as well. is it possible a injector could be doing that?


the perrin big maf fit just great. i didnt get a coupler with it, i had 1 laying around that i used and it fit great
sujorosa is offline   Reply With Quote
Old 04-23-2008, 12:42 PM   #8
sujorosa
Scooby Newbie
 
Member#: 146739
Join Date: Apr 2007
Chapter/Region: NESIC
Location: Connecticut
Vehicle:
1999 Camaro z28
Red

Default

bump.....
sujorosa is offline   Reply With Quote
Old 04-24-2008, 05:02 PM   #9
sujorosa
Scooby Newbie
 
Member#: 146739
Join Date: Apr 2007
Chapter/Region: NESIC
Location: Connecticut
Vehicle:
1999 Camaro z28
Red

Default

crank case might b the issue? i think the pvc line is blocked.
sujorosa is offline   Reply With Quote
Old 04-24-2008, 07:45 PM   #10
EJ20_lee
Scooby Specialist
 
Member#: 106799
Join Date: Feb 2006
Chapter/Region: MWSOC
Location: 6 Star motorsports
Vehicle:
2004 built 257 tomei
powered ^.^

Default

Quote:
Originally Posted by sujorosa View Post
spray water on the coil packs? any more info on this? never heard of doin that b4 thx
you will see spark jumping. i used to do that on distruributor type to check them wires!
if you see jumping on the wire, it will be the wire or go to shop and they are going to check with scanner to see misfire data and misfire counts! on 3k rpm!
EJ20_lee is offline   Reply With Quote
Old 04-25-2008, 01:36 AM   #11
silversubie02WRX
Scooby Specialist
 
Member#: 178269
Join Date: Apr 2008
Chapter/Region: NWIC
Location: WA
Vehicle:
2002 WRX
DOMtuned

Default

My guess would be you have bad coil packs or they are cracked. Not sure if its the same, but in my maxima the same thing would happen.

-Alex
silversubie02WRX is offline   Reply With Quote
Old 08-07-2008, 05:29 PM   #12
sujorosa
Scooby Newbie
 
Member#: 146739
Join Date: Apr 2007
Chapter/Region: NESIC
Location: Connecticut
Vehicle:
1999 Camaro z28
Red

Default

Fuel pressure issue it turns out.
sujorosa is offline   Reply With Quote
Old 08-08-2008, 01:01 PM   #13
ptirmal
Scooby Specialist
 
Member#: 82243
Join Date: Mar 2005
Chapter/Region: Tri-State
Location: Philly
Vehicle:
07' Acura TL-S
11' Ducati Monster 796

Default

What about fuel pressure? Did you get it fixed?
ptirmal is offline   Reply With Quote
Old 08-12-2008, 04:53 PM   #14
Teraldinho
Scooby Newbie
 
Member#: 120707
Join Date: Jul 2006
Chapter/Region: SCIC
Location: Hermosa Beach CA
Vehicle:
2002 Impreza WRX
Silver

Default

Please follow up. Did you replace the fuel pump?
Teraldinho is offline   Reply With Quote
Old 09-29-2008, 05:57 PM   #15
sujorosa
Scooby Newbie
 
Member#: 146739
Join Date: Apr 2007
Chapter/Region: NESIC
Location: Connecticut
Vehicle:
1999 Camaro z28
Red

Default

Hey sorry I forgot about this post! I didn't get it fixed. My friend bought the car and hes getting some parts together to swap to see if it fixes it. Sounds like the fuel rail or the regulator so far. I'll def post once we figure it out!
sujorosa is offline   Reply With Quote
Old 11-01-2008, 07:35 PM   #16
STIBungy
Scooby Specialist
 
Member#: 51684
Join Date: Jan 2004
Location: CO
Default

I fixed a customer's car that had misfire issues. The problem was the AP fuel rails.
STIBungy is offline   Reply With Quote
Old 11-02-2008, 11:37 AM   #17
byroll01
NASIOC Supporter
 
Member#: 611
Join Date: Dec 1999
Chapter/Region: Tri-State
Location: Saratoga Springs NY
Vehicle:
'05 E55 AMG
GetADomTune.com

Default

Quote:
Originally Posted by STIBungy View Post
I fixed a customer's car that had misfire issues. The problem was the AP fuel rails.
what did you do to fix it? Reinstall stock rails or go to another aftermarket? My friend just rebuilt his rebuilt motor (cracked cylinder) but this problem is still there. He has the AP fuel rails.
thanks


Any update from the OP?
byroll01 is offline   Reply With Quote
Old 11-02-2008, 01:28 PM   #18
STIBungy
Scooby Specialist
 
Member#: 51684
Join Date: Jan 2004
Location: CO
Default

Removed the rails and went back to stock. A shady local shop sold him a bunch of things he didnt need and did a poor job installing them. At first, I thought it may be due to the leaky fittings but after sealing everything up, the misfire was still there. I also did the obvious troubleshooting as well: new plugs, switched coil packs around, etc.

Quote:
Originally Posted by byroll01 View Post
what did you do to fix it? Reinstall stock rails or go to another aftermarket? My friend just rebuilt his rebuilt motor (cracked cylinder) but this problem is still there. He has the AP fuel rails.
thanks


Any update from the OP?
STIBungy is offline   Reply With Quote
Old 11-03-2008, 04:46 PM   #19
ciper
Scooby Guru
 
Member#: 15543
Join Date: Feb 2002
Location: san francisco, ca
Vehicle:
90BJ Legacy LS ABS
AWD 946 Rio Red Jpn built

Default

Do you have an open source cable? If so could you data log a short run where the problem exists?
ciper is offline   Reply With Quote
Old 12-09-2008, 10:52 AM   #20
byroll01
NASIOC Supporter
 
Member#: 611
Join Date: Dec 1999
Chapter/Region: Tri-State
Location: Saratoga Springs NY
Vehicle:
'05 E55 AMG
GetADomTune.com

Default

Quote:
Originally Posted by STIBungy View Post
Removed the rails and went back to stock. A shady local shop sold him a bunch of things he didnt need and did a poor job installing them. At first, I thought it may be due to the leaky fittings but after sealing everything up, the misfire was still there. I also did the obvious troubleshooting as well: new plugs, switched coil packs around, etc.
We FINALLY decided to give the fuel rails a shot and I guess that was it. The stutter/misfire was gone as soon as we pulled out of my street. He hasn't thrown a CEL in over a week since the install.

Thanks for the info STIBungy!!!
byroll01 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
04STI swap w/ misfire around 4k please read log bstoehr83 Factory 2.5L Turbo Powertrain 12 10-22-2009 09:55 AM
04STI swap Misfire around 4K rpm, what can i log to rule out fuel components? bstoehr83 Open Source Reflashes 5 10-20-2009 09:52 PM
Jerk around 3000rpms sti_my05 Other Engine Management 5 10-03-2006 08:16 AM
misfires,misfires,misfires eatsrice Engine Management & Tuning 6 08-04-2004 08:47 AM
First post: Outback with hesitation/misfire around 30mph rba007 Service & Maintenance 3 02-29-2004 02:36 PM


All times are GMT -4. The time now is 02:50 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.