Did a quick search didn't find the answer I was looking for. :roll: but it was real quick I'd like to get someone to help with a compression then leakdown test. Anyone with the tools and knowledge?
Meh, <<<had misfires since purchase at 46,000. Subaru techs clear the codes and say they don't know what it is. Only thing that I've seen fitting the description was MNStylinwrx's 'burnt exhaust valves.'
Did your car actually studder or chug? mine runs great one day and the next day it will run like crap
It did the first time it happened about 2 months after I bought it while I was working down in Kansas City. They replaced the ecu and sent mine in to be reprogramed by Subaru. I would get Brian to take a look at it. It might be something different all together. But mine needed the ecu replaced. The car still, to this day, throws random misfire codes from p301-p304. And I technically just a few hours ago, installed the fourth ECU that has graced my bugeye. It will be flashed to stage 2 this evening.
Yeah, I was thinking that it wasn't as common with your MY. But you do have a decent set-up on the stock motor...could be burnt valves. I'll be hoping for the best for you though. Burnt valves I hear are spendy! Hopefully it's something simple. Brian is damn good at what he does. I'm sure he could give you the proper diagnosis.
yeah, hope he has time and able to help me. if it's burnt valves and rings I'll start shopping for a replacement motor. I was hoping this could wait until spring though:eek4::ugh:
catch you guys up to speed. New plugs, even though old ones looked great. No abnormal wear, smells, or color. still running one step colder iridium...same as the last set Swapped all four coil packs with sarah's wrx. (Yes, I'm getting good at this...less than one hour for both):biggrin: No changes car runs great one day with NO issues (NO CELS, NO MISFIRES, etc... then the next day it will run like crap I'm encountering random misfire issues across all cyl. except #2. P0300 P0301 P0303 and sometimes P0304 Mostly 300 and 301 New O2 sensor. no changes (Well, it drove great last night after installation but it could've been one of those Good Days):roll:
Hmm, sounds similar to the issue I was having. My car would run great, and the next minute, it would spit and sputter and then stall. They swapped the ecu's and I only got the cel's. Still get them and they are very spiratic. Ex.:misfire cylinders 1 and 3, misfire on 2, 3, and 4. Misfire on 1 and 4. Pretty much any combination of those. But the car runs fine. If yours is spitting and sputtering, I would do nothing short of scheduling a time to get Brian to look at it.
bov line works pretty well. make sure you give it plenty of time to soak! 3/4 of a can is probably too much, but may be needed in your case, maybe do half, smoke out the neighborhood, repeat
walk me through this if you could.....it's been alone time since I've done this 1. car idling 2. sip 1/2 can of seafoam in bov/intake line 3. rev car to 2k or so to keep from stalling (2nd person) 4. once sipping done (sounds like I'm drinking) shut car off for 5-10 minutes 5. start car and let the neighborhood smell my smoke. 6. repeat
Also make sure that you pour in the stuff VERY SLOWLY. I've been able to seafoam my car without any outside help in the past.
Dave, more than likely won't be able to idle while sipping. It makes the car run really rich. Give her some gas while pulling it in, and make sure it pulls it slowly. Too much at once can mean disaster.
there is a vacuum line/hose right in the front of the manifold.. PERFECT that way it will distribute pretty well evenly through all intake runners.. I have seen where other guys suck it in and I am NOT convinced that it even gets to the passenger side of the car seeing as it is in one of the intake runners on the drivers side... I also have a little gizmo somewhere that allows you to suck in pure liquid or suck in vapor
seafoamed the car with no issues. sip, wait, sip, wait..........etc etc I was entertained with the smoke screen:biggrin: Found out I have a leak on the passenger side exhaust manifold/cross pipe gasket area. Typical-> Car ran great after the treatment. No cels, no misfires. I went out for a nice drive and put on about 20 miles with no misfire issues. However, later in the drive I did a WOT pull in 3rd and heard detonation. Not cool. FYI- I've heard this once before and I know if you can actually hear the popcorn poping...there's big issues. When i got home i let it idle for a couple minutes....smooth, not rough, no issues. Then I let it sit for 10 minutes and started it. Immediately runs rough for a minute then it goes back smooth idle. (No cels) I'm going to get the compression test done asap. If that doesn't uncover the issue I'll get some logs.
Have you noticed when you are getting the misfires? As in, noticed what throttle positions they are happening at?
Yes and no. 90% of the time the car MUST have recently been driven and shut off for a few minutes. In other words I drove the car until it's warm, shut it off, then started it. That's when i get 90+% of misfires, rough idle, and cels. (AT IDLE) Once the car is driven again for a few blocks it will go back to normal. Intake temps cold = runs smooth Intake temps hot = misfires Otherwise on the highway or even street driving it's fine.
Hmmm, I wonder if the intake air temp sensor is flaking out perhaps? Did you try swapping out MAF sensors?
did you try moving coil packs around? specificly move the one that has never thrown a code to one that does it the most and see if it moves the misfire
quick question.. if I had a burnt valve or leaky head gasket wouldn't this thing misfire almost all the time instead of every other day?
yes and no, you probably dont have a blown headgasket.... but if you had a really badly burned exhaust valve it would misfire all the time, i would definatly do a leakdown test and listen for air coming out your exhaust
just an update: swapped MAFs with Sarah and my car has run great since.....(but it's only been a day):roll: still noticed knock during 3rd and I'm using shell v-power 100% of the time of course. Even I thought it was nutz for doing this, but I did it anyways....decided to throw a couple small bottles of STP Octane Booster in the tank. Now there's NO audible knock and the car feels like I picked up a bunch of missing horses. I know....knock = reduced timing = lost hp. still need to log and do the tests and mointor the misfires
good times fella, it is winter gas season, chances are even the best shell gas isnt so great around this time
