51 replies to this topic

[fixitguy50]

Need some advice:
I have a 99 legacy with 266K that got a bad case of piston slap about 12K ago on a two day road trip in fall where I let it run 1 quart low. I thinking about rebuilding, as the noise makes me reluctant to take it on the road again. Since most of the noise goes away after its warmed up, I don't think I damaged the rods and mains. I've replaced the oil pump, water pump, timing belt, tensior and idlers and tried STP and Mobil 1 high mileage. Still the noise continues.

I've rebuilt other engines in the past, but not yet a subaru engine. If it just needs bearings, rings, and valve seals it should be pretty cheap for another 100K and will allow me to maintain my practice of keeping a car until its old enough to drive itself. What do you think ?

[Fairtax4me]

One quart low on oil for a short time is not enough to cause significant damage.
I don't think the 2.2 is prone to piston slap. Regardless, piston slap is not something that just starts out of the blue. With that many miles it's likely a worn rod bearing.

[Frank B]

It may be neither, it could just be a lifter. I would take it to a Subaru mechanic, someone that has experience with these engines, and have them listen to it before you decide on a costly rebuild.

Go buy some Marvels Mystery Oil and put some into the engine oil then drive it. If it's a lifter plugged up, the MMO will clean it out. But no additive will ever help if it's a rod bearing or worn piston, but you know that.

[cal_look_zero]

One quart low on oil for a short time is not enough to cause significant damage.
I don't think the 2.2 is prone to piston slap. Regardless, piston slap is not something that just starts out of the blue. With that many miles it's likely a worn rod bearing.

Mine has it on cold starts.

It may be neither, it could just be a lifter. I would take it to a Subaru mechanic, someone that has experience with these engines, and have them listen to it before you decide on a costly rebuild.

Go buy some Marvels Mystery Oil and put some into the engine oil then drive it. If it's a lifter plugged up, the MMO will clean it out. But no additive will ever help if it's a rod bearing or worn piston, but you know that.

It's a 99, it should have the SLAs.

[Frank B]

It's a 99, it should have the SLAs.

Oh yeah

[987687]

It's generally agreed that if the knocking noise goes away when the engine is warmed up, and doesn't knock when it's under load. The engine is fine.

Now if you're getting a knocking under load... that's bad. Rod bearing most likely.

[ivans imports]

late model 2.2 uses short pistons i c lots that slap its a diferent sound than the rod u do not here the rod bering when its gone because the piston hits the head before the rod berring fails compleatly and that is verry noisey i just knurll the nosiey piston and put it back in problem is gone or replace it i do an oil preshure check first should be better than 15 psi hot at idle if lower berrings are tierd cant be any lower than ten psi

[GeneralDisorder]

Piston slap is benign and being 1 quart low wouldn't cause it.... Many Subaru engines develop this eventually when the coating wears off the piston skirts. Rebuilding it will not even solve the problem. You will have to have the skirts coated/knurled or replace the pistons which is prohibitively expensive. Just live with it - it's not harmful.

GD

[fixitguy50]

Thanks for you comments guys! Where do I screw in a direct reading oil gauge ?

[GeneralDisorder]

Thanks for you comments guys! Where do I screw in a direct reading oil gauge ?

Rear oil gallery plug. It's a plug the size of a quarter - flat on top with an alan socket hole. It's just about right below the TPS on the top of the block. You can order a kit online that replaces this plug with the one used for the idiot light switch and comes with a flare fitting adaptor and a length of braided SS hose to run to your sending unit, etc on the firewall...

GD

[fixitguy50]

OK, so I've also been having a problem with acceleration on the low end that comes and goes and the engine not wanting to turn over on occassion and then turning over fine (good battery, starter). I checked the fuel pressure and got 36 psi at idle and 44 with the hose for the regulator disconnected. The book says should be 26-30 at idle and 34-38 with regulator disconnected. Do I have a bad pressure gauge or a bad regulator or what ? Most of the engine noise goes away when the engine warms up, but not all of it. Of the sounds that remain after warm up, I think its coming from the vlave train or can bearing. The valves are properly adjusted and have never been more then 0.002 out (solid lifters on 99). Compression test showed 210 on #1, 180 #2, 190 #3, 195 #4. #2 was slow to build pressure and pressure increased immediately with oil added to cylinder (classic bad rings). I saw carbon and oil in intake manifold last week when I pulled off the throttle body to clean it and then replace PVC valve and cleaned hoses of excess carbon. So, I still thinking rebuild. Anyone know a goot machine shop in the Charlotte area and a good source for parts ?

[fixitguy50]

Ok, so I did a compression test this weekend and got 210 psi for #1, 180 for #2, 190 #3m 194 #4. #2 was slow to build pressure and built pressure much quicker after adding oil. Classic ring problem. The piston slap or whatever it is can be heard at a lower level at idle after the car is fully warmed up. Engine has irregular problems with accelerating especially when I first press on the gas. I checked fuel pressure and got 36 psi idle (26-30 spec) and 44 psi with vacuum hose off regulator (34-38 spec). No crud ro water in fuel filter. Changed plugs. When I had the throttle body off to clean last week, I noticed soot specs and oil in intake manifold, so I replaced the PVC and cleaned its hoses. The engine is starting to no turn over on the first try and then turns over fine. Am I looking at a cracked ring or valve train problems ?

[ivans imports]

have found that the piston slap is created when the drilled oil holes in the piston plug up there are 4 small holes behind the oil ring if they plug the piston gets no cooling oil and wheres down the side

[fixitguy50]

OK, I put a direct reading pressure gauge in and got 20 psi at hot idle and 75 psi when reveed up. It sitll has piston slap for the first 3-5 minutes of startup and taps continuously. As regular as the noise is I'm wondering about the cam bearings or other worn valve compnents. What's weird is that the noise sounds like it comes out of the engine core, but the oil pressure is hign. Can anyone tell me what they think is going on. Do I need to swap the engine?

[Fairtax4me]

Fuel pressure sounds normal. The specs in the manual are MINUMUM pressure readings. Slightly above those is fine.
Oil pressure sounds fine.
Have you checked valve lash?

[fixitguy50]

I checked the valve lash about a year ago and tweeked it a little (.002-.003) on a couple of valves. It has solid lifters, so that's not the problem. I don't think the problem is in the bottom end since the oil pressure is good, the vacuum gauge reading are good, and it doesn't sould like a rod knock.

[darsdoug]

Do you have video/audio capability you can post?

[GeneralDisorder]

It's just piston slap - its an EJ22 - run it till it blows.

It's strikes me that you are much too sensitive to engine noises. This is not a swiss watch nor a Ferrari V12 and should not sound like either. It's an inexpensive 4 cylinder engine that will most likely outlast your wildest dreams if you just calm down, change the oil, and drive the car.

If it blows get another engine - they are cheap. In the meantime if something is on the way out there is nothing you can do to prevent it and in all likelihood it will take tens of thousands of miles to kill it anyway - perhaps hundreds of thousands. Just chill and see what happens.

GD

[oregoncoast]

It's just piston slap - its an EJ22 - run it till it blows.

It's strikes me that you are much too sensitive to engine noises. This is not a swiss watch nor a Ferrari V12 and should not sound like either. It's an inexpensive 4 cylinder engine that will most likely outlast your wildest dreams if you just calm down, change the oil, and drive the car.

If it blows get another engine - they are cheap. In the meantime if something is on the way out there is nothing you can do to prevent it and in all likelihood it will take tens of thousands of miles to kill it anyway - perhaps hundreds of thousands. Just chill and see what happens.

GD

nicely put.

[fixitguy50]

OK, so I think I patched the EJ22 as long as I can, plugs have soot coating them, it's been banging for 18 months, the compression is low on cylinders 3 & 4, and its got 280K. So, who can tell me where I can get an EJ22 for a 1999-2001 Legacy with decent mileage in the Carolinas or on the net ?

[GeneralDisorder]

You don't put an EJ22 in those model years - you go to the EJ251/3 because it's much more common and usually cheaper.

Swap over the 2.2 manifold, crank and cam sprockets, and drop it in.

Check www.car-part.com for engines in your area.

GD

[fixitguy50]

So what the difference between a EJ 22 and an EJ251/3 ? Same displacement ? Will the computer work with the different engine ? Same crank, pistons and heads ?

[GeneralDisorder]

It's a 2.5 with 30 more HP. The computer will not care. As I said use the crank and cam sprockets and manifold from the 2.2. Other than that its a direct swap - the engines look identical on the outside.

GD

[Ricearu]

won't he need the exhaust manifold from the 2.5?

[987687]

won't he need the exhaust manifold from the 2.5?

Yes, but they're easy to come by, and lots of aftermarket support.