piston slap?

[bugeyes]

My 97 obs has this knocking sound thats at its worst on cold starts. This has been going on for around a year, but has gotten gradually worse over that time. The noise is now present even after a long warm up but is only heard inside the car. When cold you can hear it inside my house....

At first I thought it was a loose timing belt tensioner... Got that replaced along with my belts during the end of summer to no avail. Now I think it might be either piston slap or a loose bolt on the torque converter (yes its a 4eat). Any thoughts?

[maddbmxjumper]

well,   it could be vavle knock also,   but it may sound stupid but check your oil,   if its not that and its not valve know from low oil,  then piston slap isnt a good sign,  that means your cylinders are worn,  and the only way to fix that as far as i know is to pull the engine and atleast hone it if not bore it and in stall new rings and possibly pistons,  but you should check the bolt on the torque converter before you go through the trouble of pulling the headand the engine.

[bugeyes]

As soon as it gets warmer out Im gonna check the torque converter bolts... definetly not the oil cuz I change it myself and just started using amsoil. If it is piston slap Im gonna pull the engine and get an ej25

[robp117]

I'm bringing back this thread because I recently solved a similar noise on my car.

Thought it was piston slap at first, then valves. It was pretty scary loud on the bad days, other days it wouldn't do it at all. Tempature didn't really matterbecause some warms summer days it would knock. Come to find out it was a hydraulic timing belt tensioner that leaked. My car is still under 50k miles and back to not making the cold knock, for now. Hope this helps!

[BlackParis]

I'm bringing back this thread because I recently solved a similar noise on my car.

Thought it was piston slap at first, then valves. It was pretty scary loud on the bad days, other days it wouldn't do it at all. Tempature didn't really matterbecause some warms summer days it would knock. Come to find out it was a hydraulic timing belt tensioner that leaked. My car is still under 50k miles and back to not making the cold knock, for now. Hope this helps!

50k!

LoL im @ 45k! in just under 2 years!

[byroll01]

my rs knocks pretty good when it's cold.   been doing it the last 2 winters and it's starting up again with this years weather.  it burns through a little oil between changes and I can tell when it's low because it gets louder.  funny thing is...my driveway is angled a little and if I park so the nose is lower it knocks alot less.  anyway, i told the guys at north country imports and they told me not to worry. I guess alot of 2.5's do it. some get warranteed but other just live with it.

[BlackParis]

Bringing this back cause w/in the last month my car has begun *grinding* on startup.. Also I noticed my lower radiator hose is dripping when I changed my oil...I actually did it @ 3500 miles, but I only drained about 2.5 quarts out... Dont know where the rest went... Perhaps I need to take a trip over to subaru to see what I can get waranteed... im @ 47600 so I got another 19k b4 my warantee ends

[BrunOfOne]

yeah i have this too, although thou can only hear it inside the car with the radio and air off. even the air blowing at 2/5 power downs it out. the guy at new country subaru gave me this....

[thegonz]

my 98 obs does this as well

only when the motor is cold

i gotta change the oil sometime soon maybe that will fix it

[skyphix]

my 98 obs does this as well

only when the motor is cold

i gotta change the oil sometime soon maybe that will fix it

It probably wont, but don't be discouraged - my car has 217,000 miles and has had Piston slap as long as the previous owner could remember (he put 100k on it after his mom put the first 100k on it).