Subaru WRX Forum

Subaru WRX Forum (
-   Cylinder Head & Short Block (
-   -   piston slap + spun bearing? (

agileblue 04-01-2012 07:21 PM

piston slap + spun bearing?
Ok, so my car is at the dealership and has piston slap in cylinder 4. I'm worried they didn't check to see if the bearing was spun either. Is this something any sane person would check if they saw piston slap going on? I mean, I know the two sound very similar, and I'm worried they just stopped the diagnostic once they saw that the piston had wiggle room. I also don't know enough to know if they took the engine far enough apart to see the rod bearing - I mean I'm pretty sure all they did was take the cylinder head off.

What is normally replaced when you have piston slap in one cylinder?

I'm calling tomorrow but was curious tonight and they are closed. I thought maybe some of you guys wouldn't mind throwing your .02 cents in here. ;)

wagonracer 04-01-2012 08:43 PM

You can feel a spun bearing with the head off, meaning you don't have to pull the pan to confirm the failure. They would replace the piston, and button it back up. If they missed a spun bearing you shouldn't have to pay them for the tear down. Be patient....

Now I'm curious what the symptoms were when you took it in. A spun bearing (rod knock) gets louder with revs, where piston slap can quiet down after the engine reaches temps. What was the car doing ?

agileblue 04-01-2012 10:14 PM

It's under warranty, I would just feel bad for these guys to do the work, put the engine back together, and then the noise is still there. I'd also be kinda ticked because I want my car back. But I'm being as patient as possible, and that's not my forte - unless I'm training dogs - what I do for a living which takes a hell of a lot of patience.

At an idle - nothing. If you weren't pushing it you had to listen carefully. If you brought it high into the rpms you could really hear it, and it was fairly loud.

I first noticed the problem on my way to work in the morning - 7 am, car had been sitting at least 8 hours. I drive to work 4 times a day on a very windy road - so needless to say I have a lot of fun with it daily. I let the car warm up for about 5 minutes before I go anywhere. I let it cool down for about 5 minutes before turning it off. But anyway, that day I stopped driving the car and took it in later in the week. I didn't want to screw up whatever was wrong with it - so the problem didn't get worse, it stayed the same. Hope thats enough info for ya! :)

wagonracer 04-02-2012 05:12 AM


At an idle - nothing. If you weren't pushing it you had to listen carefully. If you brought it high into the rpms you could really hear it, and it was fairly loud.

That description certainly sounds more like a spun bearing. Good thing they put you in a loaner !

pzr2874 04-02-2012 05:36 AM

No need to let it cool for 5 minutes, if you beat on it right up to pulling into the driveway, MAYBE a minute or so.

Glad it's coming together.

agileblue 04-02-2012 08:48 AM

Cool :D So I've wasted at least a couple hours of my life twiddling my thumbs waiting for my car to "cool down" for 5 minutes. And me too, I can't wait to have my car back.

wagonracer I agree I think it sounds more like a spun bearing too. But what do I know? I'm just a little girl. :p Anyway, I'm going to ask them more about it today when I take their weirdo forester back up to the dealership so they can run the codes. I wonder if they'll be a bit annoyed I'm pestering them about looking further? I know a spun bearing is A LOT more work for them. But I was kinda hoping they'd replace the short block anyway. ;) Plus wouldn't that mean I get a new oil system and a few other things? Lol I can see why they might have wanted to stop at just some piston play

eta: Went in they showed me my engine quickly and let me know it's getting a new shortblock. :)

wagonracer 04-02-2012 05:00 PM

[quote=agileblue;278123] Plus wouldn't that mean I get a new oil system and a few other things? [/quote]

Unless they are complete idiots, then yes you'll get a new oil cooler, oil pump and all new gaskets throughout. If it were mine, I'd offer to pay for a valve adjustment while they've got it apart, which is a small price to pay for a new engine (essentially) Shouldn't cost more than a couple hours of labor, plus the shim kit, otherwise you might be paying a lot more for it later. Same goes for the t-belt and components, it'll save you labor to pay to have those parts replaced now. Warranty won't cover either, but if you offer to pay, it's money saved later (and shows that you want everything done right !)

Unless I read your other thread wrong the car has around 94K on it. Pay for the belt and other stuff now. You'll be glad you did.

agileblue 04-03-2012 12:46 AM

Don't they have to adjust the valves for the new engine anyway? I would think they would have to do that.

I really, really, really wish I had the money to pay for all the stuff to be done now. But I don't - I'm broke as hell because I just quit a job that payed well but the owner and I were not and never will be on the same page. So, whilst I regret leaving good money, I am happier in the long run. My poor car will have to do without for now. Though I get what you mean, it's at 94k and needs that stuff done sooner rather than later.

I need a new clutch in around 5-6 months. Don't they have to take everything apart for that too?

brfatal 04-03-2012 01:06 AM

Have them do the clutch/flywheel now if you can weasel em into it. They might not since it's warranty work. If you can do it, it should be no additional labor.

agileblue 04-04-2012 12:01 PM

They called me this morning and offered to do all that stuff for no labor charge - just parts.

Apparently my clutch was pretty much toast. He said something about it being almost down to the rivets. Anyway, so it's having it's 105k maintenance done and the clutch replaced right now. They're putting it all together today and might have the engine back in the car by the end of the day.

pzr2874 04-04-2012 02:09 PM

Nice... pretty much a new car by this weekend....

turmic 04-04-2012 07:33 PM

Glad you and paul avoided the tornados down there. That would've sucked.

pzr2874 04-05-2012 05:45 AM

They didn't come close to SA... Dallas got jacked.

I could see it now... go out in the AM and there's a boulder sitting on my hood.... haaha

turmic 04-05-2012 10:17 PM

You just would've looked at it and just said, "FML!" !Laugh!

agileblue 04-06-2012 10:31 AM

LOL. So what's the boulder story, Paul? Did you take a subie out in the dirt and hit a large rock? o.O

All times are GMT -5. The time now is 03:56 AM.

Powered by vBulletin®. Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging v3.0.8pl1 (Lite) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

For the best viewing experience please update your browser to Google Chrome