I just "found" this group and it is good to find some Subaru owners and fixers :) I have a sound like hydraulic valve when I start the engine. It goes away fast and is less obvious when starting the car with the engine warm. Also a ticking at speed when cruising. Less when accelerating or slowing down. Has anyone had these symptoms and managed to narrow them down to a cause. This has been going on for over a year without getting worse. Dealers want to remake or replace the engine. Noise is also loud when fast idle in neutral. I am pretty sure this has been brought up before! The ticking could be THAT piston slap.
Ticking could be piston slap, it could be something worse though.
The "hydrolic valve" sound is it a whine or more like a hiss? The hiss is supposed to be the fuel pump preasurizing the fuel line. (You can get that by turning the key to the notch just before it starts and listening.)
If its a whine that goes away after a bit then you might have your alternator checked. Mine did that in the cold and finally blew.
Thanks for the input. By the hydraulic sound I meant the noise you hear when the hydraulic lifters are sticking or your oil pressure is low. It sounds exactly like low oil pressure at start up, then a few seconds later it goes away. The info I have been able to pick up is the valves have solid lifters, so I have ruled that out EXCEPT some places say in the 97 model year they used hydraulic lifters on some models. The road speed ticking is more than likely piston slap. If is is low oil pressure it could be that oil pump O ring I have read about! Still not sure. DO you know of any 97's with other than mechanical valve lifters?
I don't recall which years are involved - but a noisy TB tensioner is a know problem with a few soobs. See if it seems to come more from the front of the engine.
try also searching for piston slap and noisy tensioner at
IF your engine turns out to be one w/ hydraulics, the noise you heard is so common w/ Subies (at least the earlier ones) it's even noted in my owners manual ('90.) Their only advice is basically "if the noise doesn't go away after a few minutes, see your dealer." In other words, as long as the noise goes away fairly quickly, you're doing ok.
Many "cures" have been prescribed, but you can start with simple stuff. Get an OEM oil filter. Some owners (myself included) have noted a reduction in startup noise w/ OEM filters. Don't ask why, it just happens! If I had to guess, I'd go with better anti-drainback valves for starters.
"Doctor in a can" treatments sometimes help if the lifters are gummy: Rislone and Marvel Mystery Oil have been suggested and reported to help. I've used Rislone in the past, and did note some improvement for a while.
Leaky O-rings on the oil pump are often implicated, but that's much more work to cure, and isn't guaranteed any more than other ideas.
Now, if you engine's got solid lifters, have you checked the valve adjustment? My experience w/ loose valves indicates the noise will usually still be present when the engine warms up, which sounds like something you've experienced, too?
Piston slap may be on the list, too, but I'd look at simpler explanations first.
The noise goes away quickly, a couple, maybe 5 seconds. Just loud! I also read the timing belt tensioner could be the problem, it appears it gets it's tension from oil pressure. Thicker oil, like a can of "restore" seems to make a difference for a while. I'll try a some detergent should the gum on the valve works or the tensioner be the problem. Thanks for the help.
Not sure that this applies to your car but in my wife's car, the loud engine was caused by a worn out o-ring that goes where the oil pump sump/strainer tube assy. meets the engine block. The flattened/worn-out oring would somehow allow for the oil to be drained back to the carter or for air to be sucked in.
Replacing the oring, a p.i.t.a for having to remove the carter, took care of the problem magically.
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