cue Posted October 26, 2021 Share Posted October 26, 2021 Started with a misfire in #4. Went through everything, plugs, swapped coils, swapped injectors, still misfire in cylinder #4. Performed a leak down test and my compressor couldn't keep up with the air loss. Rotated the crank to see if maybe I didn't have it at TDC, no change. Performed the test on cyl #2, performed great, only 3 psi loss. I think it's an intake valve, but want to identify for certain what the failure is, so I can proceed accordingly. 2010 legacy gt, no mods, 122k miles Link to comment Share on other sites More sharing options...
islandborn Posted October 26, 2021 Share Posted October 26, 2021 If its a valve.... you will lose compression. Easiest way to tell, you idle rough. This is what happened to mine - I melted the edge of one - complete loss of compression. I originally thought it was a ringland or piston (rebuild time) but, a tech recognized the symptoms and threw the "valve" possibility. I didn't have any smoke out the back which was another point towards a bad valve. A quick pic of the valves showed it. Hope this is what you have - much cheaper to fix. Link to comment Share on other sites More sharing options...
dgoodhue Posted October 26, 2021 Share Posted October 26, 2021 Likely it is a burnt exhaust valve. If you did have a broken ringland or a hole in the piston, you will be able to feel air pushing out of the oil fill when the compressor is attemping to fill that cylinder or when the engine is running. Link to comment Share on other sites More sharing options...
Infosecdad Posted October 26, 2021 Share Posted October 26, 2021 You could try a bore scope through the spark plug hole to see if you can identify an issue with intake or exhaust valves; that's worked for a few people. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 26, 2021 Share Posted October 26, 2021 My bet is on a burnt exhaust valve as well. Link to comment Share on other sites More sharing options...
GTEASER Posted October 26, 2021 Share Posted October 26, 2021 If you are still on the stock tune its a burnt valve. GTEASER's 2012 Legacy GT - Sold GTEASER's 2009 XTeaser - Sold GTEASER's 1992 Legacy SS - Sold Link to comment Share on other sites More sharing options...
cue Posted October 27, 2021 Author Share Posted October 27, 2021 Looks like you guys are right. I had a homemade smoke machine that I made for my jetta tdi. Anyway, put cyl #4 back at TDC and put smoke to it. Had smoke coming out of the tailpipe. What am I looking at cost wise to fix this, assuming it's a burnt valve? I'm going to have to pay a shop to do it, I don't have the time to do this myself. Are we talking new head or just replace/reseat the valve? Link to comment Share on other sites More sharing options...
dgoodhue Posted October 27, 2021 Share Posted October 27, 2021 You should be able to replace the valve/machine the seat, however all the rest of your valve are not far behind from burning. So you need to adjust the all valves. The machine shop I go to charges me $1000, $500 for new valves and $500 for the assembly, repurchase the hears, clean up of the seat. I asked him why he doesn't adjust the valves with the shim buckets, he said it is just as expensive to replace the buckets as it is to replace the valves, replacing the valves pretty much bring the tolerance back to specs. For the bad new news, you have to pull the motor. You might as well replace the clutch and timing belt/water pump while it is out unless they have been just replaced. If you are in the rust belt you will likely need to replace a few parts as well. With a clutch, timing belt, engine gasket kit, it is going to be at minimum $1000 and probably closer to $1500 in parts in addition to the head work. I would imagine the shop labor is around 24 hours. This could easily be a $5K+ with $100/hr labor Link to comment Share on other sites More sharing options...
cue Posted October 28, 2021 Author Share Posted October 28, 2021 Bought a cheap boroscope to look in the cylinder. These pictures are pretty low quality but the best I could do with what I have. One pic is upper cylinder wall near the head and the other is the top of the piston. I'm guessing my best bet is a new engine. What's the best option there? What I'm seeing on new rebuilt is $7k. Way more than I want to spend. Low mileage used? Never know the condition. Or jdm import. Need the cheapest but reliable option. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 28, 2021 Share Posted October 28, 2021 Sometimes, these marks could look worse than they really are. It could also be from piston slap especially if it is at the top or bottom of the cylinder. It's hard to tell from the pic. I remember troubleshooting a misfire on cylinder 2 on my 06. Also bought a cheap borescope and saw something similar. I sure thought I needed a new block. Then I decided to check the valve clearance and found out that I had an exhaust valve with zero clearance! Fixed the clearance. After 40K miles, still running fine with no misfires! If you really want to change the block, then just go EJ257. I think these are still around 2K. Link to comment Share on other sites More sharing options...
cue Posted October 28, 2021 Author Share Posted October 28, 2021 If you really want to change the block, then just go EJ257. I think these are still around 2K. I'll definitely look closer when it's pulled. Don't know much about these engines yet. Is the ej257 an older model? Is it plug and play with my car and any changes in hp/torque? Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 28, 2021 Share Posted October 28, 2021 The EJ257 is the short block used in the Sti and is a little cheaper than the EJ255 which came with our cars. Although earlier years (05, not sure about 06) were basically EJ257 IIRC. You get a slightly better block with the EJ257. It may end up change the compression a little but it should be fine in the end. I am running the EJ257 'type RA' in one of my cars and it's just fine. And yes, it is plug and play. No real change in hp/torque. Edit: I keep forgetting this is a 2010-2014 LGT thread. What I wrote above should still be fine though. Link to comment Share on other sites More sharing options...
whitexc Posted October 28, 2021 Share Posted October 28, 2021 I just paid around $2700 for a new shortblock for my 2009. I haven't gotten the bill for the head work yet. My heads needed valve guides and seals.....apparently the valves were all ok. I am way deeper than I wanted to be into this car but it essentially rust free and only has 71k on it. I figure now we dhoukd get a bunch of years out of it and no payment is good. I went and upgraded the turbo, up pipe, downpipe.....blah blah blah. It adds up quick, even just shooting for longevity and not HP. Sent from my SM-G996U using Tapatalk Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 28, 2021 Share Posted October 28, 2021 Dang, 2700? That's a lot. I paid 1800$+ 100$ shipping I think on ebay. That was back in Dec 2019. It came from Heuberger in CO. It was a type RA block. Just did a quick search on ebay. Still from them but is now much higher. Inflation? https://www.ebay.com/itm/133564338233?epid=13035386808&hash=item1f190e1039:g:GegAAOSw0p5fblvG Link to comment Share on other sites More sharing options...
whitexc Posted October 28, 2021 Share Posted October 28, 2021 That was shipped but yeah......things are a bit excessive price wise at the moment. I tried Hueburger and they were no longer shipping direct due to damage in transit complaints. Ended up going through Crawford. Sent from my SM-G996U using Tapatalk Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 28, 2021 Share Posted October 28, 2021 That was shipped but yeah......things are a bit excessive price wise at the moment. I tried Hueburger and they were no longer shipping direct due to damage in transit complaints. Ended up going through Crawford. Sent from my SM-G996U using Tapatalk Yep. I hate it. Link to comment Share on other sites More sharing options...
dgoodhue Posted October 29, 2021 Share Posted October 29, 2021 I wouldn't assume the motor needs to be rebuild based on the borescope picture. The cylinder hasn't firing and that could be the carbon build up from the piston that is being clean off the top of the cylinder. What is the motor's oil consumption? If around around 1000 mile per quart I would fix that while the motor is out. Link to comment Share on other sites More sharing options...
dgoodhue Posted October 29, 2021 Share Posted October 29, 2021 The EJ257 is the short block used in the Sti and is a little cheaper than the EJ255 which came with our cars. Although earlier years (05, not sure about 06) were basically EJ257 IIRC. You get a slightly better block with the EJ257. It may end up change the compression a little but it should be fine in the end. I am running the EJ257 'type RA' in one of my cars and it's just fine. And yes, it is plug and play. No real change in hp/torque. Edit: I keep forgetting this is a 2010-2014 LGT thread. What I wrote above should still be fine though. I would recommend the factory EJ255 for the 10-12 though. The prior EJ255/Ej257 is missing an oil pan bolt that 5th Gen has and I read that one of the oil pan bolt hole is slight off so it also can't be used. The 5th Gen has different pistons as well. The service manual says it has higher compression, but I haven't confirm that yet (I have seen contradicting information) Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 29, 2021 Share Posted October 29, 2021 The prior EJ255/Ej257 is missing an oil pan bolt that 5th Gen has and I read that one of the oil pan bolt hole is slight off so it also can't be used. The 5th Gen has different pistons as well. The service manual says it has higher compression, but I haven't confirm that yet (I have seen contradicting information) So 5th gen cannot any of the EJ257 then, based on that oil pan bolt hole difference you mentioned? Link to comment Share on other sites More sharing options...
dgoodhue Posted October 29, 2021 Share Posted October 29, 2021 So 5th gen cannot any of the EJ257 then, based on that oil pan bolt hole difference you mentioned? People have used EJ257 block, they just leave 2 bolts out or drill and tap one of the bolts. I read the casting is thick for the bolt holes too, but I can not confirm that. I only have 2010-2012 EJ255 motors. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 30, 2021 Share Posted October 30, 2021 I see. Link to comment Share on other sites More sharing options...
cue Posted October 30, 2021 Author Share Posted October 30, 2021 I wouldn't assume the motor needs to be rebuild based on the borescope picture. The cylinder hasn't firing and that could be the carbon build up from the piston that is being clean off the top of the cylinder. What is the motor's oil consumption? If around around 1000 mile per quart I would fix that while the motor is out. About a quart per 3k miles Link to comment Share on other sites More sharing options...
cue Posted October 30, 2021 Author Share Posted October 30, 2021 Trying to find a good video or write up on removing this engine. I'm only coming across earlier generations or different platforms. Is the engine removal the same for other models or day 4th Gen legacy? Link to comment Share on other sites More sharing options...
silverton Posted October 30, 2021 Share Posted October 30, 2021 (edited) Is there a picture side by side comparison of these oil pan differences? From my experience the 255 and 257 case halves are identical castings. the difference is the crank (some times it's nitrided) and the piston crowns. the 257 has an everrrrr so slightly higher compression ratio over the 255. I should clarify. they aren't always identical. some 255's only have one block breather port, 257's generally always have two. Edited October 30, 2021 by silverton Link to comment Share on other sites More sharing options...
dgoodhue Posted October 30, 2021 Share Posted October 30, 2021 Trying to find a good video or write up on removing this engine. I'm only coming across earlier generations or different platforms. Is the engine removal the same for other models or day 4th Gen legacy? There is 'walk (talk) through on engine removal in this section'. I can't imagine it being all the different than the 4th gen. The biggest difference is that you want to disconnect the exhaust manifolds, turbo, and turbo connections and remove them from underneath not with the motor. The engine has 1 motor mount in front, the other 2 'motor mounts' are on the transmission. Link to comment Share on other sites More sharing options...
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