What does rod knock sound like?

"1337HPMustang" (1337hpmustang)
10/18/2014 at 11:48 • Filed to: Subie quest

I'm going to check out a '96 jdm STI (V3) and I'm wondering if you guys can tell me what to listen for if I'm worried about rod knock, bad bearings, pre-detonation and leaky gaskets? It'll probably be a loud car and I'm worried the exhaust might hide these problems. I know when buying used you want to hear a car at cold startup and full throttle up to redline to catch any squealing and pre-detonation but I honestly don't know what rod knock and misfiring, and pinking sounds like on these cars and I'm worried I might miss it. Thanks, have a wickety wow gm8 (not the one I'm buying)

DISCUSSION (12)

Kanaric > 1337HPMustang
10/18/2014 at 11:53

You could always take it to a subaru dealer and get a ppi if you are worried.

Arch Duke Maxyenko, Shit Talk Extraordinaire > 1337HPMustang
10/18/2014 at 11:55

Does it sound like a diesel? Then you have issues.

ly2v8-Brian > 1337HPMustang
10/18/2014 at 11:58

It sounds bad

Exhaust won't hide that.

AMGtech - now with more recalls! > 1337HPMustang
10/18/2014 at 11:59

Save the engines! Don't full-throttle when cold! Sure, blip it a bit, but wait until until the oil has been circulating for a couple minutes.

Rod knock sounds like someone hittingthe inside of the engine with a hammer, not like a sewing machine sound. Often worse when hot because the oil has thinned out. Usually present at idle and when revving, but not while maintaining higher rpm's.

These are just general ideas, I know nothing about Subaru's.

1337HPMustang > Arch Duke Maxyenko, Shit Talk Extraordinaire
10/18/2014 at 12:10

Well I know what ticking sounds like, I've got an old beater crv with bad valves on palliative care that sounds rather diesely. I kinda know what a bad engine sounds like on a typical i4 or v6/v8 but I have no clue what a bad boxer sounds like and I can't really tell from youtube videos.

1337HPMustang > Kanaric
10/18/2014 at 12:11

ppi?

1337HPMustang > ly2v8-Brian
10/18/2014 at 12:13

Thats a good video, thanks. I watched a whole bunch and I always feel I wouldn't be able to tell because video sound never does actual sound justice.

1337HPMustang > AMGtech - now with more recalls!
10/18/2014 at 12:15

Ok good to know, thanks for the tip. And obviously I'd wait until it's warmed up to proper operating temp before full throttle up to redline under load... I'm not a sadist.

Kanaric > 1337HPMustang
10/18/2014 at 12:17

pre purchase inspection

1337HPMustang > Kanaric
10/18/2014 at 12:22

ahh, yes apparently it was inspected rather recently and passed so no obvious problems. I'm worried about more subtle noises that I won't know whether they're problems or not (my mustang sounds like a bucket of bolts because my clutch and two piece driveshaft chatter but that doesn't mean anything is wrong with it).

Arch Duke Maxyenko, Shit Talk Extraordinaire > 1337HPMustang
10/18/2014 at 12:30

Google search a diesel boxer. Compare the two.

1337HPMustang > Arch Duke Maxyenko, Shit Talk Extraordinaire
10/18/2014 at 12:47

I had no idea subaru made diesel boxers, they sound super cool. Thanks for the tip.