Boost_addict Posted April 4, 2013 Author Share Posted April 4, 2013 Long-winded update… I was able to get a compression test and leak-down test performed on the front two cylinders last night. I don't have time right now to mess with the rear cylinders since the spark plugs are so much more of a PITA to remove. On an ice-cold engine I think the numbers are reasonable. I had some trouble tightening my old compression tester in the super deep spark plug pockets, so my compression numbers might even be higher than what I'm reading here. I added a bit of oil to the cylinders and the numbers didn't go up more than 1-2psi. I am assuming the #1 cylinder is on the passenger side and #2 is on the drivers side… #1: 138psi, 20% leak #2: 132psi, 18% leak When I pulled the #2 spark plug I thought I found the answer for the cylinder #2 misfire code I've gotten a couple times after all the work I did. The insulator on the new #2 plug was full of cracks. I swapped the new #1 plug to #2 and put in the best old plug (which still looked fine) into #1. I also found one of my maf-to-turbo worm gear clamps was super loose so I was hoping a pre-turbo leak might have contributed to my idle issues. No luck though. After re-assembly and starting the car it ran/idled just as poor as ever when cold (maybe worse actually). After it warmed up to full temp it runs good though. After the IAM was 1 in LV I did a handful of WOT pulls in 2nd and 3rd gear and wasn't able to replicate the misfire so I had hoped that was solved (LV was perfectly quiet on flkc). I did get a CEL with no flashing cruise after one long pull but after turning the car off and going to get my laptop the CEL went away and LV could not find a stored code. This morning I when my coolant temp was around 60-70C I got on it a little bit in heavy traffic and immediately got another #2 misfire DTC, so its much more sensitive (just like the idle) to temperature. Not sure what to do now. First I'm going to re-pressure test the system now that I have the TMIC and intake gaskets replaced and hunt for any straggling vac leaks. My LV doesn't suggest leaks though (actually the opposite I believe). Tempted to have a local subaru shop (speed industry) replicate my compression/leak down #s on a warm engine and do the rear bank too before I look at the #2 injector or coil pack. The misfire CEL is so hard to replicate (only happens when slightly below full coolant temp when I'm not trying to drive hard) so just swapping #1 and #2 injectors/coils might be difficult to show a trend. It might be faster/easier to just buy a new coil and a new (or cleaned/flowed) injector and put them in #2 (one at a time) and see if that fixes the idle and/or misfire? A subaru guy on one of my mitsu boards suggested TGV gaskets or just deleting the TGVs as a next step. If it is carbon fouling/valve deterioration I wonder if it would be too late to install water injection on the car. Every turbo car I've owned or worked on with a water injection system (or car I've run e85 on for that matter) has had absolutely spotless valves/seats/piston crowns. To summarize action plan: - Pressure test again - Clean maf a third time (seems to run/idle a bit better right after cleaning) - Get shop to verify and finish compression/leak down testing??? - Swap #2 and #1 or #4 coil/injector or replace with new??? - TGV gaskets? - Other? Link to comment Share on other sites More sharing options...
Max Capacity Posted April 4, 2013 Share Posted April 4, 2013 I vote for get the shop to do the compression test, my guess is burnt valve. Sorry 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
Boost_addict Posted April 4, 2013 Author Share Posted April 4, 2013 I vote for get the shop to do the compression test, my guess is burnt valve. Sorry The funny thing though is I'd expect relatively equal valve degradation in each cylinder if thats the case, right? Even though my cheapo harbor freight tester said ~ 20% leak it was all through the rings and NONE detectable through the exhaust (valves) at the tailpipe (but a plastic bag over each tailpipe and listened as well)... Link to comment Share on other sites More sharing options...
xt2005bonbon Posted April 5, 2013 Share Posted April 5, 2013 Mmmhh. My bet is on valves as well. Either burnt or out of adjustment. But like Max capacity said, you should probably do another comp/leak down test. Good luck man. Link to comment Share on other sites More sharing options...
Boost_addict Posted April 8, 2013 Author Share Posted April 8, 2013 I re-pressure tested yesterday. No sign of any pressure leak. I installed a new plug into #1 since I picked up a replacement and since the engine was warm I re-compression tested #1. No big change warm. I did notice a bit of brown crud in the post-maf intake tube after pressure testing. Im assuming/hoping its just some oil or worst case some condensation/collection from the air compressor during pressure test. I'm dropping the car off at Speed Industry on Thursday morning to have them verify compression and leak-down test the car warm and get their $0.02 on what could be wrong. They do a lot of Subarus and have always been honest/good to work with when I've needed dyno time in the past so hopefully they can contribute to the troubleshooting. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted April 9, 2013 Share Posted April 9, 2013 Fwiw, the shop who's working on my car confirmed that valve clearance on mine is too tight. Symptoms were just about the same as yours. Link to comment Share on other sites More sharing options...
Boost_addict Posted April 9, 2013 Author Share Posted April 9, 2013 We'll see what the shop I'm taking it to on Thursday has to say. So a few guys (or more in this thread alone) have reported "tight valve clearances" resulting in poor running performance. I'm assuming the out of spec valve clearance has to be due to degraded exhaust valves (erroded/worn seat faces it sounds like). All of my valvetrain experience is in DOHC roller rocker/cam follower with hydraulic lash adjuster setups, so I'm not 100% familiar with this subaru motor yet. I have a hard time understanding valve clearances "tightening" after 70-80k miles, but we'll see. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted April 9, 2013 Share Posted April 9, 2013 Apparently, some guys mentioned on the forum that the factory set them a bit tighter than specs so that the Subaru ticking noise is not as loud . We have valve lifters (see item 9 on pic below). If valves are out of specs, you must change the valve lifters to get the correct clearance. If I understand it correctly, a tight valve clearance means that the lifter are too thick and as a result, the valve cannot close properly. Link to comment Share on other sites More sharing options...
Boost_addict Posted April 10, 2013 Author Share Posted April 10, 2013 Not much of an update, I'm simply waiting to take my car into the shop tomorrow for compression/LD testing. I found something interesting last night though. I had read quite a few times here that even a simple non-OEM reusable panel filter can cause tune issues so for the heck of it last night I pulled the k&n panel filter out of the car (which hasn't been cleaned for probably a year) and after cleaning the mas/maf yet again I drove around the block with the filter out of the car. It seemed to idle noticeably better. I cleaned the k&n and re-installed and won't have a chance to drive the car again until tomorrow morning (wife has it today). I had mostly forgotten the car even had a k&n in it since it was there when I bought it. For the heck of it I'll pull the LV tonight as well and see if a freshly cleaned k&n changed fuel trims at all. Surely its not that simple, but would be ironic. I'm still anxious to get the compression/LD data tomorrow. Edit, this did nothing. Car still ran like crap the next day, LOL. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted April 10, 2013 Share Posted April 10, 2013 I'm still anxious to get the compression/LD data tomorrow. ^I know how you feel... Link to comment Share on other sites More sharing options...
Boost_addict Posted April 12, 2013 Author Share Posted April 12, 2013 I picked my car up last night from the shop. I have mixed feelings on the service/results. I specifically asked for compression and leak-down testing on a warm engine in order to help diagnose my rough idle condition. I gave them a list of everything I've done so far (summary of this thread basically). They did the compression testing but I suspect it wasn't warmed up properly since cyls #1 and #2 results were a bit lower than what I tested. They claim they stopped after compression testing (didn't do leak down) because all cylinders were consistent at ~ 128psi and because they diagnosed that coil #2 was bad via low resistance on the secondary. I didn't see a coil resistance spec in the FSM but I'm going to trust their judgment and replace the #2 coil as the next logical step. They said the #2 plug was wet with unburned fuel and that is the most likely the source of my rough idle and consistent with my occasional #2 misfire. We'll see. I still wanted the leak down to know overall engine health but at least they only charged me for what they actually did. If that fixes this problem then I can at least deal with the low compression at a later time. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted April 12, 2013 Share Posted April 12, 2013 If it is indeed just a coil issue, then that is great news. I hope that is the case. As for the compression results, from all the reading I've done on this forum and NASIOC, the most important piece of info is that all numbers are close to each other (+/- 7 psi or so). This is more important than the actual numbers you're getting. Link to comment Share on other sites More sharing options...
Chris GTO TT Posted April 12, 2013 Share Posted April 12, 2013 I had suspected it was a bad coil pack based on your post on our other board 2003 Baja 5MT 2016 Outback 2.5i Premium w/Eyesight Link to comment Share on other sites More sharing options...
rob-2 Posted April 12, 2013 Share Posted April 12, 2013 I had a bad idle which has been completely resolved by moving coil pack from 4th to 3rd. I cannot explain why it fixed the problem, but idle has smoothed out, no misfire in cyl 4 AND I found the dealership glued the connector onto the plug. I typically narrow things down by doing most likely and free/cheap things first. Link to comment Share on other sites More sharing options...
Boost_addict Posted April 13, 2013 Author Share Posted April 13, 2013 New oem coil should be here ~ Tuesday. I'm happy that its #2 since thats pretty easy access Just hope thats the real fix. I'd really like to keep the obxt for a while longer! Link to comment Share on other sites More sharing options...
minitech Posted April 13, 2013 Share Posted April 13, 2013 I too have seen a bad coil on EJs cause that fault, i would certainly try that and see what happens. That will probably fix your issue if the plug is not burning fuel. Link to comment Share on other sites More sharing options...
Boost_addict Posted April 16, 2013 Author Share Posted April 16, 2013 Nothing good to report. New OEM coil arrived. I replaced coil #2 which the shop claimed tested bad and had a fuel-wet plug. ECU reset by battery removal. Started car and no difference in idle (idled like crap). Thinking maybe the shop re-installed the "bad" coil on the wrong cylinder, I tested a few of them. Hot they tested around 1.5 Mohms, cold around 0.5 Mohms and no difference in the new coil or cyls #1 and #2. The only coil I didn't test was #4. Since the shop forgot to install the o2 sensor bracket on the coil #3 bolt I pulled that rusty coil by the turbo and swapped it for #1 and put the previous #2 coil at #1 (left the rusty coil off). No change in idle. I give up on coils for now unless anyone has other ideas. Its time to move onto fuel. I have a used OEM injector I’ll try swapping into #2 (I’ll do a quick ultrasonic heptane cleaning on it first). I am grasping at straws now. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted April 16, 2013 Share Posted April 16, 2013 So can you summarize with a bullet point lists all the stuff that you've done so far? I gather new spark plugsnew coil packsnew intake manifoldno vaccum leak (though not pressure tested?) So you have injectors left then? IIRC, you got a CEL on #2. Then you could swap injectors #2 and #4 and see if the CEL follows. If it does not, then.....you know. Edit: if CEL does not move after 'playing' with the injectors, I'd check the valve clearance. I believe it can be done without removing the engine. Link to comment Share on other sites More sharing options...
Boost_addict Posted April 16, 2013 Author Share Posted April 16, 2013 Summary of findings and what I've done/tried: - Datalogs/Learning View tests - adding fuel at idle? - Cleaned maf (3 times) - Cleaned air filter - Seafoam via BOV/CBV hose and gas tank - New intake manifold gaskets - New spark plugs (OEM NGK iridium SILFR6A) - Pressure test #1 - leaking TMIC (fixed via bullet-proof mod) - Zip-tied notorious blue vacuum T under TMIC and other vac/boost lines - Re-pressure tested to 15psi - no leaks - Rev limit raised from 750 to 900 rpm hot via Ecuflash - Compression test and leak-down testing on cyls #1 and #2 (cold engine): 135-140psi and < 20% LD (rings) - Cyl #2 misfire is random - idle or WOT and only once every week or two - Compression re-tested by shop on all cylinders - low but all within a few psi - Shop said coil resistance was low on #2 and plug wet with fuel - I tested #1 #2 #3 and new coil and had similar resistance (between the only two coil pins that had a resistance value) - New OEM coil on #2 - no change in idle - Moved #2 coil to #1 and #1 to rusty #3 - no change in idle Yeah swapping #2 and #4 sounds like a good idea in theory. I just wish I could reproduce the misfire more often so I could eliminate the issue. I hate driving the car day after day with the idle like crap. I've never touched side feed injectors before, but they look super simple to remove compared to a conventional fuel rail setup - remove torx screw and swap? Link to comment Share on other sites More sharing options...
xt2005bonbon Posted April 16, 2013 Share Posted April 16, 2013 remove torx screw and swap? Correct, after depressurizing the system of course (pull fuel pump fuse, turn on car, let it run until it dies, then crank it like 6 times). Link to comment Share on other sites More sharing options...
xt2005bonbon Posted April 16, 2013 Share Posted April 16, 2013 After reading your list, I'd really do what I said in my post #43: 1. play the 'swap' game with the fuel injectors and see if CEL moves to next cylinder. 2. if CEL does not move, then time for valve clearance check even if leak down test showed leaks towards rings. Link to comment Share on other sites More sharing options...
Boost_addict Posted April 16, 2013 Author Share Posted April 16, 2013 After reading your list, I'd really do what I said in my post #43: 1. play the 'swap' game with the fuel injectors and see if CEL moves to next cylinder. 2. if CEL does not move, then time for valve clearance check even if leak down test showed leaks towards rings. Since injectors are so simple to swap in this car and I have a spare injector simply replacing #2 with the spare to see if idle is immediately improved might be faster than swapping #2 and #4, which would take days or weeks to get a result? If there is no change in idle then I could swap the original #2 with #4. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted April 16, 2013 Share Posted April 16, 2013 Since injectors are so simple to swap in this car and I have a spare injector simply replacing #2 with the spare to see if idle is immediately improved might be faster than swapping #2 and #4, which would take days or weeks to get a result? If there is no change in idle then I could swap the original #2 with #4. To be honest, when I had problem with #4 I did not play the swap games and directly replaced injector #4 with a new one. CEL unfortunately remained in #4. I left the new one there and kept the old one. So in your case, if there's no change I would just leave the new one in place. No need to swap injectors IMHO. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted April 16, 2013 Share Posted April 16, 2013 I can also add that it did not take days or weeks for me to get a result. CEL came back a few miles later after having done the swap . YMMV though. Link to comment Share on other sites More sharing options...
rob-2 Posted April 16, 2013 Share Posted April 16, 2013 Did you have oil in your intake? Replace PCV.... resolved my misfire and as of this AM no oil on start up Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.