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Test drove Outback- What is this sound?


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I looked at a '97 Outback today that I think has some issues. The owners brother did mention the engine makes a tapping sound. It did get a little quieter when it warmed up, but the sound is still most noticeable at idle. I attached a video of the engine at idle for anyone that would like to weigh in the sound. The owner said a mechanic had aid valve noise? maybe piston slap? maybe a rod knock?

 

The other odd thing was that the car was set in front wheel drive (the brother knew about the fuse under he hood but seemed to think that it meant 4WD and said he had driven around in the snow this winter that way. I gave up trying convince him it is front wheel drive). My question here is if the car has torque bind (one tire was brand new and the other 3 fairly new- I wonder how long that type of thing has gone on) would putting the fuse in to make it run in FWD mask thew symptoms of torque bind?

 

I test drove it and it drove fairly well. I did notice a little pulsating in the steering wheel (maybe noticeable because it was in FWD). Other than the noise, the engine ran smoothly. The headgaskets were recently replaced and there were no bubbles in the overflow tank. The car otherwise drove pretty well, is rust free and except for a couple of dents is physically in pretty nice shape for $1,500.

 

Video of engine idling is at this link: 

https://drive.google.com/file/d/0B8N4p9BHK2dTcm1RNnBPUFl1RDQ/view?usp=sharing

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That's a rod knock which is common on the 25D since they are prone to severe overheating... IMO, project car. $500 at best if the body is that nice, but in Virginia their easier to find than here in NY so it might not be worth that at all..

 

I gave $1,400 for a pretty nice Forester S. Has 220k miles and a piston slap when cold but I drive it every day.

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I was thinking it was piston slap when the guy first said it gets better when warm, but the video was taken when it was warm. Sounds pretty deep in the engine- am thinking rod knock also.. 

 

This is a lot different sounding then the lighter tick that our '98 EJ22 Legacy makes (only under  load and only when it's cold, then it pretty much disappears) I have always considered this to be piston slap.

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Sounds like the tensioner for the timing belt. Remove timing cover and watch the tensioner. If it's flapping about, it's bad.

 

Rod knock will stay even with RPM and won't really go away, especially once the bearing has been chewed.

Edited by Bushwick
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My 95' makes some noise when cold, then quiets. I'm fairly certain mine is a tensioner issue as well. It doesn't increase with higher RPM, which rod knock will.

 

 

Forced FWD my 95' runs and handles differently. Dash light will illuminate "FWD" when fuse is in, and go out when AWD is restored. 

 

I'd check the tensioner (just remove half of the timing cover and watch the tensioner). Google "bad tensioner Subaru" and see what a bad one is like to compare to. I'd also drive it again with that fuse out so it's doing AWD. If guy doesn't want to, either pass on it or ask him to humor you. It's clearly stated in the car's manual what that is and how it works ;)

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Did you try revving it at the throttle body? Or are you saying you could hear it knock inside at all speeds?

 

I've only had two rod bearing failures and both knocked in unison to RPM. Last time was an 86' Cougar with Ford's 3.8L after doing doughnuts in the snow and redlining (many years ago) it a few times. It started knocking almost right away and was LOUD and knocked badly regardless of RPM and never quieted. I think it died within 50 miles but it made quite a ruckus then died.

 

I've seen a few posts here where people run a thinner oil than suggested by manufacturer and they end up with a noisier tensioner and posting about their knock. Wouldn't hurt to at least rule it out, as it's an easy enough fix and would be an excellent bargaining point to get the car cheaper, which if the body and interior are decent, might be worth it, but you need to rule out torque bind too.

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I did rev it at the throttle body actually. It got a little noiser as it revved up and the noise faded at higher RPM's.

 

I'm thinking a rod knock would get louder proportionally with increase in RPM's- is that correct?

 

Actually the guy selling the car said a mechanic told it him was valve train noise or a noisy rocker. He sent me a message saying another perosn who came to look at the car also had a '897 Outback with the same noise (but louder) and said it was a valvetrain/ rocker noise.

 

If it's nothing serious, tempted to see if the guy can remove the FWD fuse and put it back to AWD to see if it drives smoothly or not.

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Knocking is fairly steady at idle with rod knock. As RPM increases, the frequency of the knock increases too, but I've never had one go away completely,, with less gap between each knock. But it's also possible to have an accessory make similar noises.

 

 

Here's a Subaru rod knock that sounds similar to what my Cougar sounded like: 

 

 

 

And here's one that sounds similar to the one you are looking at, but definitely a different sound than the one you posted. He revs it near the end, so listen closely and compare, also notice how loud it is as he walks towards the rear.

 

 

Seems a bunch of people chunk their WRX engines up pushing them too hard.

 

I'd insist on pulling that fuse just verify it's working. The car's manual should clearly state how it works unless they changed something. If you have any doubt, ask if he'll meet you at YOUR mechanic with the car. Tell him if it checks out, you'd be a serious buyer, but you need to know the condition.

Edited by Bushwick
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here's a good link to noise diagnosis.

 

http://remanufactured.com/Engine_Diagnosis_101.htm

 

rod knock will go away when you disconnect the plug for the bad cylinder.

read up.

 

from the above link

 

 

Rod knocks are loudest at higher speeds (over 2500 RPM) Feathering the gas
pedal may result in a distinctive back rattle between 2500 and 3500
RPMs.
Bad rod knocks may double
knock if enough rod bearing material has been worn away allowing the
piston to whack the cylinder head in addition to the big end of the
connecting rod banging on the crankshaft rod journal. It will sound like
a hard metallic knock (rod) with an alternating and somewhat muffled
aluminum (piston) klock sound.
Wrist pin knock in modern engines is very rare today but is a favorite for the
misdiagnosticians.
Edited by johnceggleston
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I told the guy I was passing on it and he said another guy who has the same year Outback (making the same noise) said it was valve train noise. I figure I might take it if he ecame way down on the price but that would be all.

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Followup- I decided to look at this car again.

 

The owner did remove the FWD fuse and there is no torque bind that I could feel.

 

I took it for a much longer drive this time including higher speed roads and noticed the following:

 

A slight pulsating in the steering wheel on acceleration (like torque alternating between wheels or something, mainly under harder acceleration

 

A sound like water sloshing around coming from the heater core area (heat and A/C both worked fine)

 

transmission seemed a little late shifting into 4th (this is a 4EAT) on occasion- at one point I questioned whether it went into 4th at all, but another higher speed drive did get it shifting into 4th several times

 

The car seemed sloid and drove fairly well for a $1,500 car athis point and my wife and I agreed to make the purchase... however...

 

When we pulled up in fron of the seller's house I decided to listen to the engine tap again and immediately noticed coolant gushing out from under the radiator cap. The seller had pointed out the cap (a generic unlabeled aftermarket cap) fit somewhat loosely and needed to be replaced with the proper Subaru cap. He said since he was having issues with it that he plugged the coolant overflow line.

 

At this point I'm wondering if it was just the cap or was the recent headgasket job failing (you could physically see the edge of newish gaskets when looking at the engine). He said he had replaced an earlier non- original cap, then refilled and burped the system and it hadn't been overheating lately. Whatever it is, it seemed like the longer higher speed drive we took helped with the overheating.

 

In any case he felt bad about it and will try to get a new Subaru cap ASAP.

 

So does it sound like a failed recent headgasket job or just a bad cap?

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Did you by chance see water bubbles in the radiator over flow tank?? Bubbles will look like what you see in a home fish aquarium. If so, that is a dead give away that the head gaskets are bad.

 

Suggest after a new rad cap is installed, drive again for some time to get the motor good and up to operating temp, then stop and look for those bubbles I just spoke about. Even if not over heating, the bubbles probably will be present indicating bad HGs

 

The tranny late shifting may possibly be fixed by changing the ATF.

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Kinda sounds like a head gasket to me, but with the overflow hose being plugged off, the cooling system has to have somewhere to vent when the coolant gets hot, it's going to just push out of the cap.

 

I wouldnt pay $1500 for it.

Agree with Fairtax...........sounds like head gaskets to me also. I think seller is playing dumb about the cheap rad cap, and over flow hose being plugged off. You won't ever know how many times the motor has over heated. I think I would pass on buying this car.

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Very likely it needs headgaskets. With the noise, assume you will do a full rebuild or swap a known good engine in. Adjust the price accordingly.

 

The gurgling water got my attention - that's a sign of low coolant. VERY bad for headgaskets. The rest of the description regarding the cooling system is a huge red flag.

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sloshing may be due to fungus or mud or insects clogging a/c drain hose.

 

who know how often or how severely it has overheated in the past even IF the noise is not rod knock NOW, it could develop in the future.

 

 

 

The only way I would buy it, is with the knowledge that it likely will need a new engine or short-block in the near future, and make an offer reflecting that.

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It would be a great candidate for a EJ22 swap as the body is rust free and clean. Problem for me is physically doing that large of a job (I'm pretty much a tune-up and brakes guy), finding a good running EJ22, and the seller is firm on the $1,500 price (although if a mechanic agrees on failed headgaskets that price could come down).

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Leaving a radiator cap loose, the system will NOT build up pressure. This is actually a trick you do to get a car limped home, like say you have a pin hole in a heater hose line, or if the radiator is clogged externally (external row fins caked with heavy mud). Engine will still run, and it'll get warm, but it won't pressurize the coolant. I wouldn't buy it as-is until you see the cap replaced and the system pressurized, then run it to temp.

 

I would install a proper cap (not you, him, or take one from one of your other cars that'll fit) and let the overflow work and drive again. If it shows signs of a HG issue now, hammer him on the price (for wasting your time). If the body/interior are good enough for an ej22 swap, you can always go that route and sell the old engine off.

 

Wish you were closer as I'd look at it for you and could help. 

 

Gotta agree with others though at this point that the seller is being a little too sneaky. I drove almost an hour south to buy my 95' which I believe the seller had been trying to sell for roughly 10 months. They lived in a rural area not easy to get to. Engine had lifter tap, and rear crossmember was completely shot, and it needed a brake line, but everything worked (heater, AC, power locks/windows/mirrors). I think they were asking $1100 or $1k. I went over the car completely, and pointed out the lifter noise, it had some exterior scratches (his mom was the owner and was in her mid 70's and getting forgetful, etc. which appeared true) and I finally said I was interested at getting it road worthy again, but would he be willing to work on the price with me as it was going to need towed + the work to get road worthy again. We finally settled on $850 (IIRC) and it's been a champ the past 3 years now and it had the ej22 and a good trans. TBH, the guy was fairly firm in the ad, but once it became clear I'd get the car running (road worthy) and take care of it, and people weren't exactly in a line to buy the car (the crossmember scared a guy off prior but he was honest about everything in the ad) he was willing to negotiate.

 

Unless the body is pristine, you are better off waiting and finding something better with a seller that isn't keeping little things from you. I know when I sell a car, I'm 100% open if it needs anything, as well as explaining what's been done to it. 

Edited by Bushwick
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