Major smoking from new motor

[shredtahoe]

Around may last year, my brother shot a rod through the block of his factory ej251 in his 02 outback wagon. We replaced the shortblock with an ej25d jdm shortblock and reused the old heads (new valves, seals, and guides). Put it all together with the ej25d head gaskets and back in the car and now the thing smokes like crazy (doesnt seem like oil, though), and the idle bounces around from 1-3000 rpms. The only codes its throwing are P0507 and P1507. Any ideas?

Also, before we got it running correctly, we had it set up with non re-done heads and ej251 gaskets and it knocked like crazy and smoked really badly then too, but it seemed like that was oil smoke. The short block was checked out at the shop where the heads were done, so I know that it is in good shape, as are the heads.

Thanks!

[Outbackid]

That brother is me. Please help us troubleshoot this.

[Outbackid]

Anyone? This needs to be adressed soon and I can't figure it out. I changed out the thermostat (I was using an old corroded JDM one) for a new one and I checked the one suspect vacuum connection for a leak and nothing helped. I'm also now getting a blinking CEL, so I haven't driven anywhere since.

[Reason]

Shot piston rings? I would do a compression test and have the codes read.

[Huffer]

You have a vacuum leak - that's causing the weird idle - the car/ECU is trying to find itself and it's can't learn the idle because it can't adjust the metered air.

As for the smoke...is it possible that you guys knocked a bunch of crud into the block that's been combusting?
If it's white smoke, it's piston ring leakage.

[r3v_v3ng3]

Timing belt installed correctly?
Did you guys had the heads check for leaks/crack from the machine shop?

[Outbackid]

Heads were rebuilt two weeks ago. Timing belt is installed correctly. I'm having a compression check done this week, and I hope to God it isn't piston rings. It's a JDM motor with low miles, it wouldn't make a whole lot of sense for them to be blown so early.

[lord flashheart]

How long has it been smoking? Most of the time when you have major engine failure(especially broken rods) it pumps a ton of oil into the exhaust. It usually takes a few hours of running for the cats to burn it all off.

[Outbackid]

How long has it been smoking? Most of the time when you have major engine failure(especially broken rods) it pumps a ton of oil into the exhaust. It usually takes a few hours of running for the cats to burn it all off.
Less than an hour's worth of driving. It was a broken rod, that could be it. I just dropped it off at a local shop to get a compression check tomorrow and see if they can fix the idle issue. It's a LOT of smoke though. How bad would it be from residual oil?

[Huffer]

Could be nothing, could be a lot. Depends on how much was dumped down there.

Easier way to tell is to disconnect the exhaust from the headers, and run the engine that way. If you get no smoke from the bottom of the block, you're good and it's just the exhaust that needs to be cleared out.

[Outbackid]

Well it's in the shop now. I really just want the idle issue fixed so I can give the smoking some time to go away or not. If it is rings, how much damage could driving it for the couple hours it may take to burn off oil in the pipes cause to the internals?

[lord flashheart]

Not much damage at all. Toyotas sometimes smoke when the pcv lines are clogged up because the pressure is builds up and pushes past the rings. But its not nearly as comon on subarus.

[lord flashheart]

Also I know you mentioned that you had new seals... But I wanted to clearify, you mean valve stem seals right? Could the machine shop fucked up and forgot to put one on? (ive seen it before)

[Dead91silvia]

I did a few motors that has smoked for about 30-45 minutes. Most of the time it's coolant in the exhaust, but sometimes oil. Mind you, I most of the time it's on none Subaru's. Worst one was an 06 Cobalt that sounded like a rattle toy when it came in.

Sometimes it can take running the car up and down the freeway all out to burn everything out.

[Outbackid]

Also I know you mentioned that you had new seals... But I wanted to clearify, you mean valve stem seals right? Could the machine shop fucked up and forgot to put one on? (ive seen it before)
It's got entirely rebuilt heads (new valves, valve guides, stem seals etc.) and those were done by a guy who does a lot of Japanese motors.


I did a few motors that has smoked for about 30-45 minutes. Most of the time it's coolant in the exhaust, but sometimes oil. Mind you, I most of the time it's on none Subaru's. Worst one was an 06 Cobalt that sounded like a rattle toy when it came in.

Sometimes it can take running the car up and down the freeway all out to burn everything out.
Hopefully that's it. I'm thinking it may have to do with EGR stuff.

[lord flashheart]

I don't think it would.
I think its residual or plugged pcv.

[Outbackid]

I don't think it would.
I think its residual or plugged pcv.
Could a PCV problem cause the idle problem too?

[lord flashheart]

It's possible. It could also be that the amount of oil being burned is fucking with the 02 sensor.

[Outbackid]

Welp, I got the car back from the shop. My rings on the driver's side are toast. May be selling the car as a roller. Not really just because of the engine, but there is some damage from a deer incident that we may just take the payout (a lot of money for minor damage) and get rid of the damn thing. We've already put in more money than we should've.

[Reason]

I wish I was wrong! Used blocks can be found for a couple hundred dollars.

[Outbackid]

I wish I was wrong! Used blocks can be found for a couple hundred dollars.
Not usable ones, at least in Iowa. The lowest miles on any Subaru in the local salvage yards is like 192k and I have never found a usable EJ motor other than that around here sub-$800. We may re-ring it though. If we do sell it, my brother (OP) may buy it and put in an EJ22 for boostability. So I don't see it hitting the scrapyard at least.

[shredtahoe]

I almost hope the parents decide they don't want to deal with it and then that car will get a whole lot more fun :grin:

[L.Michael]

Was there any reason to putting the SOHC heads on the EJ25D block?

[Outbackid]

Was there any reason to putting the SOHC heads on the EJ25D block?
No rewiring or anything. I blew the EJ251 block, simply put in an EJ25D block as a replacement. Found the problem, PCV was sucking up oil from the crankcase and spitting it into the intake. Simple fix.

[Outbackid]

Was there any reason to putting the SOHC heads on the EJ25D block?
Also it is worth mentioning that I could not find an EJ251 SOHC motor in reasonably good condition where I live, so I just got a JDM longblock.