Welcome to the North American Subaru Impreza Owners Club Sunday September 15, 2019
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo)

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 06-22-2019, 09:28 AM   #1
Theclerk95
Scooby Newbie
 
Member#: 500640
Join Date: Apr 2019
Location: Nova Scotia
Vehicle:
2001 legacy b4

Default Misfire at 6500rpm after dyno tune and lots of rain

Well a little stumped and figured may as well ask for some help before throwing parts at the car.

Car is an 01 legacy b4 rev c automatic. Primary downpipe and center pipe decat. Dw65c fuel pump. Zerosports intake pipe with apexi filter. 3 inch catback.

Just got the car back from being dyno tuned yesterday (Friday). Tune was finished on Wednesday. Was tuned using project lambda open source.

It was raining insanely hard yesterday on my drive home which is about an hour away from the shop, so I didn't get much chance to boost it or anything. But before getting on the Highway I did a quick 1st to 2nd Wot and it was fine.

After I got off the Highway I filled up the tank and headed home the rest of the way. Car seemed okay til I went to go wot again and it was boosting low around 7psi on primary and 12 on secondary and misfiring at 6k as if it was redlining.

This morning it was still wet out but the car boosted 10psi on primary and 14 on secondary but still misfired at 65k this time.

Looking for any suggestions. Theres no codes or CEL and Like I said the car didn't do it for the tuner and didn't do it until after all the rain on the Highway and after I filled up.

Gas mileage was amazing on the way home yesterday as well. 100km and barely moved the hand. Since the refill have done 30km and it's moved a whole notch.

Vacuum reads fine, and the car drives fine other than lack of power and misfiring.

Thinking maybe a wet coil pack that's on its way or maybe even a bad batch of gas. Plugs were changed around 20-30k ago with ngk pfr6b plugs

Thanks!
* Registered users of the site do not see these ads.
Theclerk95 is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 06-22-2019, 05:42 PM   #2
PVNRT
Scooby Newbie
 
Member#: 483821
Join Date: Mar 2018
Vehicle:
2004 WRX 2.0 18g

Default

Is this the first time the car was pushed a bit? Did tuner raise boost pressure vs what you had before? Sounds like ignition, but you never really know until you start replacing parts. I would start with new spark plugs maybe one step colder and properly gapped. Make sure coils have a firm connection to plugs....maybe add a touch of dielectric grease and then zip tie them on tight. If that doesn't help I would look for a loose ground and then look for boost leaks. Can be as simple as a torn intake at this mileage. Hopefully you did normal maintanence such as fuel filter before the dyno tune. Making more power than designed for will always have these hiccups unless you take the car off the road and do all normal maintenance first.
PVNRT is offline   Reply With Quote
Old 06-23-2019, 12:37 AM   #3
Fierysun
Scooby Guru
 
Member#: 82745
Join Date: Mar 2005
Chapter/Region: SCIC
Location: So Cal
Vehicle:
2005 Subaru STI
2003 EJ207 S204 Wagon

Default

Get new plugs and check ignition coils
Fierysun is offline   Reply With Quote
Old 06-23-2019, 05:51 AM   #4
Theclerk95
Scooby Newbie
 
Member#: 500640
Join Date: Apr 2019
Location: Nova Scotia
Vehicle:
2001 legacy b4

Default

Quote:
Originally Posted by PVNRT View Post
Is this the first time the car was pushed a bit? Did tuner raise boost pressure vs what you had before? Sounds like ignition, but you never really know until you start replacing parts. I would start with new spark plugs maybe one step colder and properly gapped. Make sure coils have a firm connection to plugs....maybe add a touch of dielectric grease and then zip tie them on tight. If that doesn't help I would look for a loose ground and then look for boost leaks. Can be as simple as a torn intake at this mileage. Hopefully you did normal maintanence such as fuel filter before the dyno tune. Making more power than designed for will always have these hiccups unless you take the car off the road and do all normal maintenance first.
Have pushed the car before, but it was 2 years ago that it was on a dyno last. Definitely agree that its most likely ignition. Changed the fuel filter a couple months ago and the oil right before the tune.

Tuner upped the boost a little but most of the map changes were for ignition and fueling. They never experienced any misfiring or issues when it was on the dyno for the power runs and they street tested it that night as well I guess. Only seemed to have issues after I got home off the Highway and got gas.

Have added water remover to the tank just to see if that helps. And I have 2 new maf sensors at home so gonna give that a shot just to see tonight.

If not I'll order new coils just for piece of mind and replace the plugs.
Not thinking its a boost leak as they smoke tested it before the dyno and only found one vacuum nipple leaking and fixed that. And a weld on the intercooler piping that was fixed as well.
Theclerk95 is offline   Reply With Quote
Old 06-23-2019, 10:26 AM   #5
Charlie-III
NASIOC Supporter
 
Member#: 30669
Join Date: Dec 2002
Chapter/Region: Tri-State
Location: USA, North NJ, 07456
Vehicle:
1998 Legacy 2.5GT
Silver Sleeper BK, 5MT

Default

I would be easy on boost and run that tank out and refill somewhere else. Sounds like bad gas. Waaayyyyy too coincidental that it was fine until that new gas.
Charlie-III is offline   Reply With Quote
Old 06-23-2019, 11:15 AM   #6
Theclerk95
Scooby Newbie
 
Member#: 500640
Join Date: Apr 2019
Location: Nova Scotia
Vehicle:
2001 legacy b4

Default

yeah hoping that is the case. I've added STP Water Remover, and I'm gonna run it dry and see if it helps when I fill it up next.

Going to try the new MAF Sensors as well, and order the coils so even if they aren't bad I atleast have them for when they do go.
Theclerk95 is offline   Reply With Quote
Old 06-23-2019, 02:31 PM   #7
Fierysun
Scooby Guru
 
Member#: 82745
Join Date: Mar 2005
Chapter/Region: SCIC
Location: So Cal
Vehicle:
2005 Subaru STI
2003 EJ207 S204 Wagon

Default

Make sure to gap to .025 on the plugs.
Fierysun is offline   Reply With Quote
Old 06-23-2019, 02:41 PM   #8
Theclerk95
Scooby Newbie
 
Member#: 500640
Join Date: Apr 2019
Location: Nova Scotia
Vehicle:
2001 legacy b4

Default

Quote:
Originally Posted by Fierysun View Post
Make sure to gap to .025 on the plugs.
factory gap for the ej206 is meant to be 0.65mm

edit - sorry my dumba** wasn't converting inches to mm
Theclerk95 is offline   Reply With Quote
Old 06-23-2019, 02:55 PM   #9
Fierysun
Scooby Guru
 
Member#: 82745
Join Date: Mar 2005
Chapter/Region: SCIC
Location: So Cal
Vehicle:
2005 Subaru STI
2003 EJ207 S204 Wagon

Default

Quote:
Originally Posted by Theclerk95 View Post
factory gap for the ej206 is meant to be 0.65mm

edit - sorry my dumba** wasn't converting inches to mm
I've found there's a big difference in getting a random misfire with .030 vs .025.
Fierysun is offline   Reply With Quote
Old 06-24-2019, 03:16 PM   #10
Theclerk95
Scooby Newbie
 
Member#: 500640
Join Date: Apr 2019
Location: Nova Scotia
Vehicle:
2001 legacy b4

Default

Quote:
Originally Posted by Fierysun View Post
I've found there's a big difference in getting a random misfire with .030 vs .025.
May have to give that a go! Going one step colder on the plug this time as well with a ngk pfr7b. Ordered four new Delphi packs so I'm really hoping this solves it. Only got to do one pull on the new tune.

Tried the maf sensor yesterday and that changed nothing.
Theclerk95 is offline   Reply With Quote
Old 06-24-2019, 07:44 PM   #11
Kbellew
Scooby Newbie
 
Member#: 481827
Join Date: Feb 2018
Location: Murfreesboro, Tn
Vehicle:
2002 WRX WAGON(6MT)
Silver

Default Intake filter?

I have had issues with a old/dirty intake not blocking water well. Anytime it would rain it would suck in water causing bogging of the motor/ misfire type sensation upon wot or even slight acceleration to get up to speed. If you have an older Intake filter i would say re-place that and try.
Kbellew is offline   Reply With Quote
Old 06-24-2019, 07:57 PM   #12
Theclerk95
Scooby Newbie
 
Member#: 500640
Join Date: Apr 2019
Location: Nova Scotia
Vehicle:
2001 legacy b4

Default

Quote:
Originally Posted by Kbellew View Post
I have had issues with a old/dirty intake not blocking water well. Anytime it would rain it would suck in water causing bogging of the motor/ misfire type sensation upon wot or even slight acceleration to get up to speed. If you have an older Intake filter i would say re-place that and try.
No I dont think its that the apexi filter has only been on for maybe 300km
Theclerk95 is offline   Reply With Quote
Old 06-25-2019, 01:17 AM   #13
chilakas
Scooby Newbie
 
Member#: 210354
Join Date: May 2009
Location: Kenosha Wisconsin
Vehicle:
2003 Wrx
Blue

Default

Everytime this happens to my car its the maf sensor being dirty. I spray it with maf sensor cleaner and she goes back to normal. I think that's the easiest thing to try, plus it's good to do anyway. A dirty maf never triggers a cel on my car. A ignition issue always has triggered a flashing cel when missfire is ocurring in my ecperience.

Ok saw that you tried the maf already. The other likely cause is a bad coil pack. If you have a buddy with a good coil packs swap them all and see if it goes away. If not order a good one and try swaping 1 by 1.

Last edited by chilakas; 06-25-2019 at 01:25 AM.
chilakas is offline   Reply With Quote
Old 06-25-2019, 10:45 AM   #14
Theclerk95
Scooby Newbie
 
Member#: 500640
Join Date: Apr 2019
Location: Nova Scotia
Vehicle:
2001 legacy b4

Default

Quote:
Originally Posted by chilakas View Post
Everytime this happens to my car its the maf sensor being dirty. I spray it with maf sensor cleaner and she goes back to normal. I think that's the easiest thing to try, plus it's good to do anyway. A dirty maf never triggers a cel on my car. A ignition issue always has triggered a flashing cel when missfire is ocurring in my ecperience.

Ok saw that you tried the maf already. The other likely cause is a bad coil pack. If you have a buddy with a good coil packs swap them all and see if it goes away. If not order a good one and try swaping 1 by 1.
yeah had two new maf sensors at home so gave those a go, was really hoping they would fix it lol. Yeah didn't have friends local with coils that would work to try, so I just ordered 4 delphi coils from rockauto and pfr7b plugs. Hoping this solves it.

Its an OBD1 car still, and I've found whenever somethings wrong it takes about 600km for a light and code to come on. Had a bad o2 sensor last year and just reset the code and it didnt come back for another 600km... pretty bad haha
Theclerk95 is offline   Reply With Quote
Old 06-25-2019, 11:44 AM   #15
Fierysun
Scooby Guru
 
Member#: 82745
Join Date: Mar 2005
Chapter/Region: SCIC
Location: So Cal
Vehicle:
2005 Subaru STI
2003 EJ207 S204 Wagon

Default

Try these ignition coils if you haven't bought replacement already.

http://www.offthelineperformance.com...ry&path=56_176
Fierysun is offline   Reply With Quote
Old 06-25-2019, 01:35 PM   #16
Yodes
Scooby Newbie
 
Member#: 478591
Join Date: Dec 2017
Location: Ontario
Vehicle:
02 WRX
Sedona Red pearl

Default

if your still having a problem check your plug connections cuz over the years of messing with plugs and coil packs the wires probably pretty janky or atleast the insulator around the wire is crap and lets the elements inside
Yodes is offline   Reply With Quote
Old 07-02-2019, 02:31 PM   #17
Theclerk95
Scooby Newbie
 
Member#: 500640
Join Date: Apr 2019
Location: Nova Scotia
Vehicle:
2001 legacy b4

Default

Quote:
Originally Posted by Yodes View Post
if your still having a problem check your plug connections cuz over the years of messing with plugs and coil packs the wires probably pretty janky or atleast the insulator around the wire is crap and lets the elements inside
Well just changed out the coils and the plugs to a step colder with the ngk pfr7b. And my issue is still persisting. Car did feel a little smoother but still only hitting 10psi primary and 14 secondary and misfiring at 6500
Theclerk95 is offline   Reply With Quote
Old 07-02-2019, 06:28 PM   #18
Fierysun
Scooby Guru
 
Member#: 82745
Join Date: Mar 2005
Chapter/Region: SCIC
Location: So Cal
Vehicle:
2005 Subaru STI
2003 EJ207 S204 Wagon

Default

Quote:
Originally Posted by Theclerk95 View Post
Well just changed out the coils and the plugs to a step colder with the ngk pfr7b. And my issue is still persisting. Car did feel a little smoother but still only hitting 10psi primary and 14 secondary and misfiring at 6500
Did you replace all four coils with brand new ones?
Fierysun is offline   Reply With Quote
Old 07-02-2019, 07:11 PM   #19
Theclerk95
Scooby Newbie
 
Member#: 500640
Join Date: Apr 2019
Location: Nova Scotia
Vehicle:
2001 legacy b4

Default

Quote:
Originally Posted by Fierysun View Post
Did you replace all four coils with brand new ones?
yeah all four with delphi coilpacks. issue is still the exact same, no better or worse. called the shop that tuned it and neither the owner or tuner were in, and neither are replying to my messages now. Guy at the shop is saying the issue is still there due to me using delphis and not oem diamond coil packs. If that was the case though I would imagine that it would be different now at least
Theclerk95 is offline   Reply With Quote
Old 07-02-2019, 08:46 PM   #20
Fierysun
Scooby Guru
 
Member#: 82745
Join Date: Mar 2005
Chapter/Region: SCIC
Location: So Cal
Vehicle:
2005 Subaru STI
2003 EJ207 S204 Wagon

Default

Quote:
Originally Posted by Theclerk95 View Post
yeah all four with delphi coilpacks. issue is still the exact same, no better or worse. called the shop that tuned it and neither the owner or tuner were in, and neither are replying to my messages now. Guy at the shop is saying the issue is still there due to me using delphis and not oem diamond coil packs. If that was the case though I would imagine that it would be different now at least
Why Delphi over OEM?
Fierysun is offline   Reply With Quote
Old 07-02-2019, 08:58 PM   #21
Theclerk95
Scooby Newbie
 
Member#: 500640
Join Date: Apr 2019
Location: Nova Scotia
Vehicle:
2001 legacy b4

Default

Quote:
Originally Posted by Fierysun View Post
Why Delphi over OEM?
Just what i was able to afford at the moment and what was readily available. Have never had issues with Delphi before either
Theclerk95 is offline   Reply With Quote
Old 07-04-2019, 04:44 AM   #22
Theclerk95
Scooby Newbie
 
Member#: 500640
Join Date: Apr 2019
Location: Nova Scotia
Vehicle:
2001 legacy b4

Default

Well update... Got a tuner who did etunes for me before look at the map and the tuner who did my dyno tune lowered the boost and didn't tell me. and the rev limiter he lowered by accident... Map has been changed and it doesn't misfire at 6500 now. Still has a little bit of a rough idle after driving for a while and letting it set in park. But my ecu has been reset like 15 times in the past 2 weeks so hopefully idle just needs to relearn
Theclerk95 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

All times are GMT -4. The time now is 03:54 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2019 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.