Just another misfire/rough idle thread...

OP, did I ever share the following with you?

 

I bought an identical part number ECU off ebay, and copied the rom from my existing ECU to the replacement using Tactrix 2.0 cable and ECUflash software.

 

Rom load went well, but car did not start on replacement ECU, as expected. code p1571 coming up - information mismatch... Needs key registration ceremony at dealer because of swapped equipment. So I booked an appointment.

 

THEN I learned of the single small 8pin EEPROM chip on the ECU that holds all the fingerprint data for the car ... unsoldered it from the original ECU and moved it over and soldered it onto the replacement ECU.

 

Car magically starts and runs fine. Successful complete cloning process.

 

No dealer visit required to register keys, cancelled the appointment.

 

Thanks to Tactrix support and RomRaider forum for pointing out the EEPROM chip to move.

 

 

Also, did you ever change the camshaft sensor on the driver side?

Edit: yes you did.

^ I don't remember hearing that from you, but by chance I stumbled upon that exact info this week.

 

I have a few old circuit boards laying around for just this kind of situation, so if I can get comfortable cleanly removing/reinstalling (soldering) tiny components on those old boards I might try to replace the ECU myself.

 

Sent from inner space.

So I pulled out my starter a few weeks ago in an attempt to figure out why my friend's rebuilt motor wouldn't turn over. Turns out (pun intended) I'm an idiot and forgot to connect one of the starter wires on his starter. Problem solved and his YNANSB rebuilt motor started up on the first try.

 

While my starter was out I noticed that the end of it was pretty grimy, like it was oily and dirt was sticking to it. I don't know how it could get that way unless the rear main seal is leaking.

 

I fixed my problem by ignoring it and putting the starter back in without even cleaning it off. Maybe one of these days I'll get out my borescope and look down in there and try to get past the flywheel to take a peek at the seal.

Soooo was there ever any resolution on this? I just got done having my motor rebuilt to replace a burnt #2 exhaust valve and not 5k miles later I’ve got more misfires on cylinders 3 and 4. I’ve already swapped the 1 and 3 coils but to no avail. I guess up next is an injector swap but I have a feeling I’m in the same boat as the OP. This car will fight me every step of the way until the bitter end when I leave it unlocked over night in down town Albuquerque.

I believe OP is just ignoring it and enjoying his car. Still runs fine I believe.`

I guess I’ll do the same and ignore it off a cliff

Nothing has changed, and the misfire is still alive and well in the rebuilt motor.

 

I don't completely ignore the misfire, but I've learned to run BtSsm less often so the roughness count isn't always staring me in the face saying "Look at me! I'm still here, I love you, and there's nothing you can ever do to make me leave." Of course I could always turn off the roughness count display in BtSsm... but where's the fun in that?

 

I recorded an interesting log when I was idling in the parking lot one day after work a few months ago, but I haven't looked at it yet because I've been on a good stretch lately and I'd just rather not renew my frustration. At this point I don't even remember what was going on that made me record the log, I just remember that it was idling really weird and doing stuff I don't remember seeing before. It's a really good story with crappy details.

 

The thing that kills me about my misfire is that I can always make the misfires stop just by making the car go more than 0 mph. Fowards or backward, in gear or in neutral, handbrake on or off, engine warm or cold... 0 mph seems to be the only constant. Lately I've been thinking more and more about replacing the ECU to see if that's the problem. I would have already replaced it by now if it didn't require a trip to the dealer or a nervous test of my sketchy soldering skills.

 

I get misfires every once in a while in a certain rpm range when the car is moving, but I think that has something to do with the stumble/studder thing commonly associated with our stock FPRs. I may replace the FPR with an adjustable one this summer. I'm not seeing the pressure that the FSM says I should see, so why not give it a shot? I'll probably get an adjustable FPR #BecauseRaceCar, and I'd like to be able to play around with fuel pressure to see if that does anything to the misfire condition.

 

Back in mid-December baby #5 crawled out of my wife (more or less that's how it works) and since then my non-essential car time has been reduced from 1 minute per day, to a level that's effectively equal to zero minutes per week(end). A few months prior to the baby we added a '15 Express 2500 van to our driveway, so that's also something you can look forward to if you ever decide to have more kids than normal vehicles are designed to carry. What about minivans, you say? Don't forget about huge car seats built to withstand Daytona-500 type crashes, compatible strollers for the previously mentioned car seats, normal strollers, compact strollers, bicycles, tricycles, wagons, dragons, coolers, droolers, blankets, diaper bags, pool toys, cousins, and occasional trips to Home Depot for as many bags of mulch and 2x4s that I can fit on the cart (with the 4 big kids riding along, naturally). Large vans also have ample headroom that comes in very handy during fast-developing events like last weekend's "oh my gosh, did George just throw up again?" road trip situation.

Edited May 25, 2018 by StkmltS

I have old-man amnesia but with the rebuilt engine, are the injectors all new?

In-tank pre-filter sock and in-tank fuel pump paper filter and in-engine bay (if you have it) fuel filters new?

 

 

Sounds to me that you could correlate the misfires with Injector PW/DC (try to log that and see what you get). I bet if the PW is low enough (hence the 0mph, in/out of gear, etc) then you get misfires, as soon as the PW goes up a tad because of higher RPM and vehicle speed, and the bump is providing more fuel - this overcomes the minor clog limitation and bam - no misfires. Just a theory.

 

 

 

I guess another way to test this is to artistically raise the injector PW at 0 RPM by re-scaling the injectors a bit with a smaller scalar value, but then you'd need to scale the latency too

The injectors aren't new, but one is new to the car. The misfire is semi-always in cyl#2, and swapping the injectors around to different cylinders doens't change anything. I've also cleaned them in my ultrasonic cleaner.

 

The in-tank sock is new, the pump is a almost-new dw65c, and I don't have an engine-bay fuel filter.

 

The miss happens at 0mph regardless of RPM (700, 3k, bouncing off the rev limiter), in and out of gear, clutch pedal in or out, brake pedal in or out, so would your PW/DC theory still apply? At 0mph on a hill it misses, moving >0mph it stops missing (forward or reverse... I tried it).

 

I haven't messed with the PW/DC at all since I started tuning so it's worth a shot. The misfire started on the 100% stock tune so I'm not optimistic.

 

I'm a liar... I'm optimistic and I get a little excited about every new potential-fix I hear. Roll the window down and turn the volume knob to 100% with the stereo turned off and the passenger seat heater at 50%? It's gotta work, I'll try it today!!!!!

I wish I shared your optimism. I swapped my 2 and 4 injectors around over the weekend and what was originally a misfire on 3 and 4 is now a misfire on 1,2,3, and 4. Just need this thing to not explode for a few more months while I wait for the civic type R market to die down a bit.

Update:

I threw more money at the car.

I bought a used STI fuel pressure regulator.

Right at this very moment it's in my garage waiting to get installed into the most awesomest 5-speed LGT wagon in Kentucky.

If we have good weather I'll do the old swap-a-roo this weekend.

End of update.

I ran into a huge issue on Friday... the motor stopped misfiring.

Not on the way to work, not on the way home, and not on Saturday.

No joke, it just stopped.

 

Is this car trying to push me over the edge?

Could the car sense that I'm getting close to the root cause and it temporarily suspended the symptoms just to play with my emotions?

Is my car Herbie, reincarnated?

 

The new (used) fpr will stay in my toolbox until the misfires comes back.

 

Raise your hand if you're confused and frustrated.

 

 

 

 

Hey I was wondering if your misfire still stopped? And if you have any idea what on your long journey actually fixed it? I unfortunately have a very similar misfire in my 05 outback XT. It has me to the point of frustration that I cannot enjoy this car. I have done most of the easier things to check, including a leak down test that did not show any issues. Thank you also for documenting the entire journey. Its really nice to be able to compare information from my own tests with your information!

The OP knows that I am the 'check your valve clearance guy' on the forum . Just so you know though, I had excellent cold leakdown results on two cars and yet had misfire in one particular cylinder in each car. It was due in the end to a tight exhaust valve for both cars!

The OP knows that I am the 'check your valve clearance guy' on the forum . Just so you know though, I had excellent cold leakdown results on two cars and yet had misfire in one particular cylinder in each car. It was due in the end to a tight exhaust valve for both cars!

 

 

Right, this seems like the most common cause of misfires in this engine design. Valve clearances in these engines usually get tighter with age/use, not looser. And when you notice it is when the engine fully warms up.

 

 

This being said, the OP and his car are freaks of nature (I mean that in the nicest way!), and his misfires are for some different cosmic reason.

Thanks guys, I will check that next. Also I dont know if it makes a difference to you guys, but mine actually seems to do it worse when the engine is colder, and it will also do it at light throttle. Like cruising around town in third gear, very light throttle, it will miss bad as well. But thanks again for the suggestion, I will check it soon!

Thanks guys, I will check that next. Also I dont know if it makes a difference to you guys, but mine actually seems to do it worse when the engine is colder, and it will also do it at light throttle. Like cruising around town in third gear, very light throttle, it will miss bad as well. But thanks again for the suggestion, I will check it soon!

 

Sounds like your issue is probably being caused by one of the more typical causes: plugs, coils, injectors, maybe even valves (I'm saying that one just for bonbon:)).

What makes my problem unique is that it happens/happened(?) only at zero mph, and rpm/temp don't seem to make a difference. Many of the things I've tried can be ignored most people. The cause of what makes me unique (as heiche mentioned) hasn't been investigated yet... but you can see the effects in the few threads I've started.

Edited August 10, 2018 by StkmltS

Actually, I would think his problem may be rings. As far as I understand, if you have an issue with your ringlands (e.g. very small crack), it may show up as misfires particularly when cold. But once warmed up, the rings have expanded probably just enough to restore descent compression, thereby eliminating misfires. This scenario assumes that your coil/plug/injector/valve clearance are all good. Now again, this is a possibility, not a certainty!

So my misfire isn't gone, and I don't even know if it was even temporarily gone or not.

How, you ask, do I not know something as simple as knowing if the misfire was gone or not?

 

During the few days that I thought the miss was gone, I noticed the car still sounded and felt like it was misfiring. I was happy to see "0" misfires in BtSsm so I just went with it like anyone enslaved by an attractive manual transmission turbo wagon should. This morning I decided that it was time to see what's really going on, so I reset the ECU and the misfires are back to being displayed like normal again. It was kinda fun while it lasted.

 

Why wasn't the ECU displaying the misfires (in any cylinder)?

Why did resetting the ECU "fix" the problem of not displaying misfires?

Where in the world is Carmen Sandiego?

 

This morning my fuel pressure (measured by a digital transducer, wired through the left TGV, displayed in BtSsm) was fluctuating at idle more than I've seen before (72-119 psi). I think that means either something is up with the sensor, or my pressure is wonky. A short log is attached to this post for your kind amusement. I'm logging more parameters than necessary but I don't care right now because seeing tons of confusing numbers in a spreadsheet makes me feel smart.

 

Good news: My reason to change the FPR is back.

 

Better news: I've been selling plasma twice a week and working a second job at night to afford more car parts. My oldest daughter (6 yo) told me last night that when she can drive she wants to get a wagon like mine. A tear formed in my eye and I said "NOOoooOOOOoOOOoo!", just kidding, my heart melted and I was reinvigorated to continue my fight against the evil misfire demons. I might start saving up for a new/used ECU because I haven't burnt any money over that area of the car yet.

 

This car will not beat me.

BtSsm_20180823_064629[1].csv

Edited August 23, 2018 by StkmltS

Sorry if this is posted somewhere in this thread, but did you re-route your FPR signal line yet? The stock location in one intake runner makes the fuel pressure bounce rapidly (to coincide with the vacuum pulses in that runner). Moving the signal line to a common source like the BPV signal smooths er out a bit. You'll probably see less erratic signal while monitoring your fuel pressure (still erratic, just less so).

 

 

If you already did the above mod, please disregard

 

 

The other mod of going to the later FPR seemed to cure an off idle bog when i hit the throttle. This mod as well as the above one helped driveability quite a bit.

 

 

But I never had your demon misfires, so I dunno about that.

I did move the ref line to the BPV line, and the nipple on the IM is capped off. I don't remember if I made the move before or after the rebuild, and this is a monster thread and at this point all duplicated questions will be excused. Sometimes asking the same question slightly differently gets people thinking differently, and maybe I (we) will think of something from a new perspective.

 

Even if the STI FPR doesn't fix the misfire i'm looking forward to it helping with the low-rpm bogging/stumble/studder issue. My motor definitely has that going on.

I did move the ref line to the BPV line, and the nipple on the IM is capped off. I don't remember if I made the move before or after the rebuild, and this is a monster thread so at this point all duplicated questions will be excused. Sometimes asking the same question slightly differently gets people thinking differently, and maybe I (we) will think of something from a new perspective.

 

Even if the STI FPR doesn't fix the misfire i'm looking forward to it helping with the low-rpm bogging/stumble/studder issue. My motor definitely has that going on.

Edited August 23, 2018 by StkmltS