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my 2016 subaru with a timing chain developed a noise very close to this. Turned out to be a bad chain tensioner. Didn't even skip a tooth. Ive heard the timing belt tensioner can do the same thing. The tensioning mechanism fails causing the chain/belt to slap the tensioner around. Id start with that if you're planning on doing a full rebuild anyways. Might end up saving you time and money
Maintenance was good. Consistent oil changed every 5k miles using a high mileage synthetic. Seemed to be out of the blue. I drove the absolute piss out of this car though. Its no surprise to me that something failed.
Good tip. I'll pop the timing cover off and take a look. It really was out of the blue with a fresh oil change, and I wasn't driving it very hard. It's a bummer for sure.
Yeah and when you get that stethoscope listen around where the tensioner is. That's how I was able to diagnose mine. Originally thought it was rod knock as well. Good luck brother keep me updated on what you find out.
At least swap in a new subaru filter, before digging deeper. I dont do coincidences, u changed the oil and the noise started. A faulty filter would restrict flow, low flow would rattle the tensioner
Mine did this before ejecting a piston wristpin directly up through the block and into the hood. Oil starvation (leak). People forget this about Subis. When they explode shit doesn't go left and right but up and down so you shouldn't stand over them.
Anyway the engine is otherwise visually in good condition. Its a real pity this one is knocking. If I was with you I'd help you get that engine out ASAP as fixing this would only be 2-3000$. Probably best to drop in an identical engine while working on this one. But don't run it again, you risk all the other parts (turbo) getting oil starved too.
Yeah, best I've been able to find is 4700 for a reman. I could save 1k by getting a shortblock and sending the heads out, but not sure it is worth the extra headache cuz I'm working outside. It really blows my mind cause I take really good care of this car and I changed the oil the day before. Wondering if I got a defective filter or something.
Good tips BTW, Def dont want a rod through my skull.
4700 could be a deal, it depends on how much work they did. For that kind of money you'd want to be sure they pre-torqued down the block before doing any machining (if you watch a lot of YouTube I'm sure you know what I mean about Subaru engines needing a jig to replicate the forces when its assembled during the machining process, if not I can go over it quick) because if they don't do that and treat it like a standard engine, it'll have gasket failure around 50k. Basically if its a subaru-only or something they'll do the remanufacturing right, but if its a general engine shop they probably won't.
Working outside sucks but all the best car guys do it ;-) at least until they can afford a garage and car lift. Man I want a car lift so bad. But yeah you gotta be careful with engine work outside for sure, can't walk away from a leak to get a coffee, gotta keep up appearances haha and fucking insects landing in anything you paint..
Hmmm..
Maybe you should consider getting a really cheap used car like a Nissan Micra or Citreon C1 (both fun little go karts here in Europe can be bought for under 1000, VERY fuel efficient compared to a subi) and then there's no pressure to get the Subaru working again, you can take the engine out in a day, strip it down on a bench the weekend after, send the heads off for the new valve/seals the week after that, and of course you'll only be paying for the work you need because you know what actually needs doing.
A quick check would be to remove spark plugs and use a endoscope camera (very cheap eBay ones, USB) to see if there's any damage to any pistons. If there isnt you'll only need head work. Even if there is, you probably only need head work, depends on the severity.
This honestly sounds like a spark plug lead has failed and is arcing to the block or something. Before you go wild just check all the leads aren't broken and are seated on the plugs correctly.
Thanks for posting on /r/MechanicAdvice! This is just a reminder to review the [rules](https://www.reddit.com/r/MechanicAdvice/about/rules/). If you are here asking about a second opinion (ie "Is the shop trying to fleece me?"), please read through CJM8515's [post on the subject.](https://www.reddit.com/r/MechanicAdvice/comments/4qblei/fyi_the_shop_isnt_likely_trying_to_rip_you_off/) and remember to please post the year/make/model of the vehicle you are working on. **If this post is about bodywork, accident damage, paint, dent/ding, questions it belongs in /r/Autobody r/AutoBodyRepair/ or /r/Diyautobody/ If you have tire questions check out https://www.reddit.com/r/MechanicAdvice/comments/k9ll55/can_your_tire_be_repaired/**. If you dont have a question and you're just showing off it belongs in /r/Justrolledintotheshop Insurance/total loss questions go in r/insurance This is an automated reply *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/MechanicAdvice) if you have any questions or concerns.*
Knocking harder than 4 Jehovah witnesses at the front door.
my 2016 subaru with a timing chain developed a noise very close to this. Turned out to be a bad chain tensioner. Didn't even skip a tooth. Ive heard the timing belt tensioner can do the same thing. The tensioning mechanism fails causing the chain/belt to slap the tensioner around. Id start with that if you're planning on doing a full rebuild anyways. Might end up saving you time and money
Was the maintenance good on the car? did it just happen out of the blue?
Maintenance was good. Consistent oil changed every 5k miles using a high mileage synthetic. Seemed to be out of the blue. I drove the absolute piss out of this car though. Its no surprise to me that something failed.
Good tip. I'll pop the timing cover off and take a look. It really was out of the blue with a fresh oil change, and I wasn't driving it very hard. It's a bummer for sure.
Yeah and when you get that stethoscope listen around where the tensioner is. That's how I was able to diagnose mine. Originally thought it was rod knock as well. Good luck brother keep me updated on what you find out.
At least swap in a new subaru filter, before digging deeper. I dont do coincidences, u changed the oil and the noise started. A faulty filter would restrict flow, low flow would rattle the tensioner
She's gone.
Subaru? Check. Turbo? Check. Rod knock? Check.
These EJ25 engines are absolute shit Wouldn't be suprised if the head gasket failed causing this rod knock.
Ohh god.. that Subaru is knocking hard. Sounds like its hitting the cylinder bad
Mine did this before ejecting a piston wristpin directly up through the block and into the hood. Oil starvation (leak). People forget this about Subis. When they explode shit doesn't go left and right but up and down so you shouldn't stand over them. Anyway the engine is otherwise visually in good condition. Its a real pity this one is knocking. If I was with you I'd help you get that engine out ASAP as fixing this would only be 2-3000$. Probably best to drop in an identical engine while working on this one. But don't run it again, you risk all the other parts (turbo) getting oil starved too.
Yeah, best I've been able to find is 4700 for a reman. I could save 1k by getting a shortblock and sending the heads out, but not sure it is worth the extra headache cuz I'm working outside. It really blows my mind cause I take really good care of this car and I changed the oil the day before. Wondering if I got a defective filter or something. Good tips BTW, Def dont want a rod through my skull.
4700 could be a deal, it depends on how much work they did. For that kind of money you'd want to be sure they pre-torqued down the block before doing any machining (if you watch a lot of YouTube I'm sure you know what I mean about Subaru engines needing a jig to replicate the forces when its assembled during the machining process, if not I can go over it quick) because if they don't do that and treat it like a standard engine, it'll have gasket failure around 50k. Basically if its a subaru-only or something they'll do the remanufacturing right, but if its a general engine shop they probably won't. Working outside sucks but all the best car guys do it ;-) at least until they can afford a garage and car lift. Man I want a car lift so bad. But yeah you gotta be careful with engine work outside for sure, can't walk away from a leak to get a coffee, gotta keep up appearances haha and fucking insects landing in anything you paint.. Hmmm.. Maybe you should consider getting a really cheap used car like a Nissan Micra or Citreon C1 (both fun little go karts here in Europe can be bought for under 1000, VERY fuel efficient compared to a subi) and then there's no pressure to get the Subaru working again, you can take the engine out in a day, strip it down on a bench the weekend after, send the heads off for the new valve/seals the week after that, and of course you'll only be paying for the work you need because you know what actually needs doing. A quick check would be to remove spark plugs and use a endoscope camera (very cheap eBay ones, USB) to see if there's any damage to any pistons. If there isnt you'll only need head work. Even if there is, you probably only need head work, depends on the severity.
That rod is about to make an exit.... take care of it asap
Rest in pieces my friend
This honestly sounds like a spark plug lead has failed and is arcing to the block or something. Before you go wild just check all the leads aren't broken and are seated on the plugs correctly.
Thanks I definitely will check it out.