Infosecdad

:spin: exhaust valve clearance on #3 is perfect. :spin:

I'll try to get some decent pictures and post them here. I'm getting way too good at tearing down that side of my engine bay to get to the engine...

I do... I plan to scope through the plug and the injector when I get into it next and see if I can find anything with the scope.

I worked on her for a number of hours yesterday/last night. I have most of the misfires from #1 gone. I had to replace the "cleaned/flow tested a year ago" injector with one of my older ones and it cleared up. The only time #1 misfires now is when I have a decent amount of load and #3 is mad. I'm pretty sure it's essentially sympathy pains bleeding over. I thought I found the issue when I found that the clip is busted on the #3 injector wiring plug. However, that wasn't it. I pulled the spark plug that is almost new to find that the gap was significantly less than .031. Re-gapped it, didn't make a difference. Redid the connector for #3, the pins for the coil definitely fit tight now, no change. The behavior now is that it will be running rough and sometimes registering misfire at idle. Most of the misfires are registered under load, even though it's running rough most of the time now. However, I can make a 5 min stop and when I get back out she runs perfectly for a while before returning to rough. Gas smell in the exhaust is strong, minor backfires, definitely not cleanly burning in that cylinder. After messing with it, definitely more consistently dogging and misfiring from #3. I picked up valve cover gaskets from the dealer. I'm going to reseat #3 injector one more time. And I think I'm going to pull valve cover and measure the exhaust valve clearance. I can't decide if I'm hoping this is it or not...

I do. But I don't know why it would be intermittent... I haven't found a decent explanation as to why valve clearance would be so intermittent and flip on and off like a switch and on two cylinders.

Spark plugs are new. 93 Shell or Costco Did a compression/leakdown a while ago, don't remember the numbers, but they were fine. I pulled the fuel pump, replaced the o-rings and filter. Put it all back together, no difference. Tested the fuel pressure, it's perfect at 43psi at idle and seems to be in the right ranges when revving. I've pulled the front O2 to force it into open loop to see if it's a sensor that's killing it, and it still has the issue (just doesn't record the misfires). Pulling the MAF really ticks it off, doesn't really want to idle then. I've thought about the coolant sensor, but I think we only have one on these cars and it seems to be spot on for temps. I've also thought about TGVs messing up, the sensors read good though. I need to drive it for 600 mile round trip next week, so trying to figure this out. It's not messed up all the time, just sometimes. When it goes, you can feel it; even without misfires. You can feel a "switch" thrown, and she starts bogging down and running rough. Under load misfires in #3 and sometimes #1 is in-sync with it. Then you can be driving and the "switch" flips again and she is liquid smooth. For the life of me I haven't figured out how to nail this down without firing more of a parts cannon at it...

Look to the left of your post. <—- you had 8 as of this reply.

Still pretty frustrated. Can't figure out what exactly is causing this. It's now coming and going multiple times in a trip. Can be smooth, then rough; once it's rough and there is any load I get a pile of misfires. Usually just #3, but if I push it at all (like uphill), then I can get #1 and #3 to misfire in sync. Thoughts about it are: - TGVs: Maybe they are doing something to mess up that bank? Not sure if there is much they can do, might do a delete anyway. - Fuel Pressure Damper: They could impact the rail on that side. I checked mine and they seem to be ok, tried adjusting them, but hasn't seemed to make a difference yet. - Fuel pump: I'm starting to wonder if my fuel pump is having an issue. I replaced the stock with a AEM 50-1000 in May 2017. I don't think I did a double o-ring, but not sure. It's been fine for a long time, might try testing the fuel pressure. The thought is if it's losing pressure or dying, then #3 is last in line and doesn't get what it should; then if I push it and demand more, #1 has issue as well and it's the second to last injector. - Coil Harness Plug: Pretty sure this is not it, I've double checked them three times, and the behavior of it going 1 & 3 if pushed when rough also pretty much rules this out.

I've played with them. I had to replace the connector for #3 before. I have tweaked the pins and the connector is zip tied, but maybe it's still having intermittent issues... ??? Maybe I'll try to mess with that again this weekend.

Ok, looks like I'm back for more... Running smoothly, then bam! idling like crap. Misfires on #1 and #3 again. Then clears for a while, then returns. Temp, humidity, stuff like that doesn't seem to play a part. I replaced the #3 injector with one from my original set, didn't change the behavior. Most of the time, she runs really smooth, idles smoothly, great power, just a joy. About 1 of 3 trips, she loses her mind (at least for part of the trip). Yesterday, I needed to go to Costco, about 5 min into the drive, she just goes mad. #3 is misfiring badly, worse under load. Even when misfires are registering, the engine is bucking like it's on three cylinders. Running really rich, can smell the gas, tail pipes were all sooted, backfiring when letting of at times. Sometimes #1 joins in, but this time #3 (with a replaced injector, new plugs, and new coil) is the primary. Get to Costco, mutter all sorts of stuff, go get the few things I need. Come out, start her up, purrs like a kitten. Drives like a dream for 15 min, then loses her mind for about 2 min, then back to super smooth. I'm beating my head against the wall trying to figure out what could be root cause. - It's only ever effected the passenger bank (#1/#3) - Sometimes one cylinder, sometimes both - When it's happening, the engine is running really rough (like missing a cylinder) - It can run really rough without registering any misfires - When rough, it feels like it's dumping fuel (or at least not burning it) Right now, it seems to me that a certain condition is met, the ECU freaks out and it all goes down hill. Makes me wonder if a sensor is starting to freak out. - front 02? Wouldn't that impact more that just that bank? - cam sensor? Could the cam sensor on that side be responsible for this? (probably not) - Something telling the spark plug/coil to stop firing? That would explain the strong fuel smell, rich conditions, and backfiring... - ???? sensor? And no, I haven't checked valve clearance yet. I'm not convinced that could be it based on the really intermittent behavior. I've thought about a valve sticking open, but it would be weird to have it on two cylinders. Continuing research, I'm thinking about what could be responsible for two cylinders on one side to stop firing the plug... Thoughts, ideas?

Yes, there are specific $15 cables you can get to USB to an OTG cable to the tablet. I need to go see if I can find the one I have. Or someone else may chime in before I find it.

Do you have any pictures of the power steering pump? Power Steering Pump OEM (NEW Coated w\ Enamel, Blue)

There really isn't updated equipment. The latest Nexus people really have working is the Nexus 7 2013 model. The walkthroughs for doing this are still basically accurate.

Not gonna now that it's running smoothly :-D That's basically the only scenario I can come up with as it started happening within a couple blocks of filling up. And it hit both injectors on that side. As it cleared up, it cleared on #1 in the front first, then for #3 in the back. The interesting thing is that the fuel delivery is sequential. It flows through #2, #4, #1, #3... So if something got in, it made it cleanly past 2/4 before mucking something up before 1/3, then got past #1, and finally cleared on #3. Whether it returned back to the tank or dissolved don't know. I removed the pulse dampener from the return line when I went to an STi FPR so it can't get stuck there.

OCVs are very much in alignment. I pulled the #1 plug and scoped it, what I could see looked fine. I decided to just put it back together as the family wanted Chinese carryout. So I headed out to the market first, ran like crap. #1 misfiring to 50 and reseting. #3 misfiring continuously, rolling to 100 and looping around. 8 min drive, shuddering, just pissed off. Stop at the market, idle for a min, shut it off. Get a few things, come back out, start it up. Different car, smoother, minimal misfire. Stop at autozone, get a can of liquid moly injector cleaner, dump it in the tank. Idle and running continues to smooth out. Pick up Chinese, head home, running really smooth now. Last leg of the trip, nothing more than a 2 on #1... Honestly, I'm thinking the last fill up put some crap into that injector rail or something like that. I'll keep an eye on it, but hoping that's what it was.

I considered that, but it's not consistent. It comes and goes... I think I'm going to swap in a couple of my old injectors because it doesn't take too long to do that. If that fixes it, I'll decide whether to ship off my back up set of injectors for cleaning or to go find some dw740s...

Been so smooth and good, then put gas in from Shell by my house a few days ago and within a block started getting misfires on the 1/3 side for that trip. Then replaced the radiator, first drive as smooth. Next drive it was mad, both 1 & 3 going to 100 and resetting, obvious shudder. Injector duty cycle seemed to be higher than it should be. Trying to figure out if a bad tank of gas can do that. Might swap back in a couple of my old injectors that were fine when I replaced them last year. The ones I have now where cleaned and flow tested two years ago so I hadn't been messing with them.

You can do both, I have both a blanket and headshield (x2) and so has several others. Lava blanket, OEM headshield, STi heatshield

Which year do you have? Wondering if it's a difference in a later year or not.

You've unbolted the upper coolant tank so you can shift that right? Is this the bracket that's on the intake manifold? I rotated the bracket on the OCV 90 degrees toward the outside of the engine and was able to get it past with minimal leveraging. The trick for me was to pull the first valve cover hose to get enough clearance. If you have original hoses it might shatter, so may want to plan to replace it just in case. I had replaced with new hoses a month before so it went smoothly.

Wow, when taking out my passenger side, I just had to rotate it a little bit and wiggle it at the end and it came right now. I'm curious what you are hanging up on.

It says 05-07, but that's a post facelift front end.

You can get the front crash beam or trim the corners of your USDM one. You probably also need the headlight mounting brackets as they are matched to the bumper. I did the USDM brackets for a bit, but the mounting tabs for the JDM bumper are a little different.

Yeah, I'm trying to think if there is something else that might be contributing to what I am seeing at the moment. I'm going to keep an eye on it to make sure this behavior stays consistent.

Interesting update. I was playing around over the weekend and picked up some ultra copper gasket and copper spray-a-gasket. I did a few exhaust joints downstream from the down-pipe. Then I pulled my BOV and sprayed the copper gasket on both sides of the paper-like gasket. Four trips later, the few misfires that were still present after the intake gasket are basically gone. I've seen two 6s, but only once per trip that it showed up. Couple of 1 or 2, but they are quite rare now. Might have actually had some minor leak at the BOV that I didn't know about before.