Engine Management Cobb AccessPort, EcuTek, TEC, Motec, Link, and others. The ins and outs of high-performance engine tuning.

Cylinder 4 misfire

Old 08-04-2013, 04:22 PM
Registered User
Thread Starter
Join Date: Apr 2013
Location: Kapolei
Posts: 5
Car Info: 05 Subaru STI
Cylinder 4 misfire

I own a 05 STI, when i start her up in the morning idle is good everything runs smooth up until she warms up. She then sputters as if im running rich, their is a burning smell and white smoke will come out of the oil cap when i open it. Ive changed oil (full synthetic), spark plugs, and gave her a full injector cleaning solution (probably why she smells funky). Now throughout the day, it has become more of a challenge to start her up. Id have to wait for my sti to kick over and apply small amount of gas just so she doesn't bog out. Any suggestions? ive read up that it could be my Coil Packs and Piston rings, still does that have anything to do with her starting up?
nytmrchr is offline  
Old 08-16-2013, 11:11 PM
Registered User
Join Date: Sep 2012
Location: Marina
Posts: 5
Car Info: 2003 WRX Hybrid
Hard to start car may need a new fuel filter. Or fuel pump or regulator is going out. I know it keeps fuel pressure higher until up to temp then drops it, which could be the issue. Have you done compression check? How many miles on motor? Have you checked valve clearances? A tight valve will misfire too.
paintbing is offline  
Old 08-17-2013, 09:11 AM
Registered User
iTrader: (17)
Javirex23's Avatar
Join Date: Oct 2008
Location: Bay Area
Posts: 2,178
Car Info: 07lmtd 6spd wrx eq tuned
Get a compression check. I was in a similar situation and my cyl 4 is toast
Javirex23 is offline  
Old 08-17-2013, 09:50 AM
Registered User
iTrader: (1)
tourexy's Avatar
Join Date: Apr 2011
Location: Next Door
Posts: 1,595
Car Info: 02 PSM Impreza WRX
Get a compression check mines was throwing out misfire codes as well turns out to be a bad coilpack
tourexy is offline  
Old 01-09-2014, 09:59 PM
Registered User
Join Date: Nov 2013
Location: Fremont ca
Posts: 7
Car Info: 2014 sti
Make sure u clear codes first then Swamp the coil from cylinder no 1 to cylinder no 4 see if misfire follows to no 1 if it doesnt and stay still at 4 next step would be take the compression test reading if it came low in compression and u still want to know more bring the no 4 at TDC and do the leak down test if the air is heard escaping from the tail pipe u got a bad exhaust valve if from the intake u got a bad intake valve take off the oil cap if the air heard through the crank case that means u are f u k ed bad rings good luck son
eTron is offline  
Related Topics
Thread Starter
Last Post
Suby Shopping & Maintenance/Warranty
06-23-2005 11:28 AM
Engine/Power - EJ20T (pre-2006 WRX and JDM)
04-19-2005 12:01 PM
Suby Shopping & Maintenance/Warranty
04-08-2005 06:45 AM
Engine/Power - non turbo (All non turbo Imprezas)
03-29-2004 08:29 PM
Engine/Power - EJ20T (pre-2006 WRX and JDM)
05-29-2003 11:48 PM

Thread Tools
Search this Thread
Quick Reply: Cylinder 4 misfire

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to and affiliated sites.