Subaru Legacy Forums

Subaru Legacy Forums (http://legacygt.com/forums/index.php)
-   Turbo Powertrains (2.0GT, 2.5GT, 2.5XT) (http://legacygt.com/forums/forumdisplay.php?f=12)
-   -   Just picked up a '05 OBXT and it tripped a P0021 (http://legacygt.com/forums/showthread.php?t=185521)

Mad Matt 05-10-2012 12:03 AM

Just picked up a '05 OBXT and it tripped a P0021
 
New to the Legacygt.com family. Just picked up an 2005 OBXT from a used car dealer with 104k on it. Had test driven it once before with no engine light. Last night I test drove it once more before buying it and no light. Bought it and drove it about an hour to McDonald's where I stopped on the way home. Started it up a few min later to head home and a couple minutes into the drive the check engine light came on. I have driven it a couple of time since and ran over to Autozone to find out the code is P0021 and no others. The light stays is on consistently. I have no service history, oil on dipstick is clean, engine runs smooth, slight turbo lag (but definitely getting boost), everything appears stock. Had a friend who knows engines very well listen to it and he felt that it was running fine. I read some here, and looked for the banjo filters. Pulled the vertical bolt on the drivers side where I think it is supposed to be and there is no filter in the bolt (already removed?).

There is all kinds of advice here, but I need to know quickly if I need to try to get my money back (don't really want to since my trade in barely ran and kinda love the xt), or buy one of those crappy $400 extended warranties. I need to know within hours since once the dealer submits the paperwork to the sec of state he says I can no longer buy the warranty. May already be too late.

Anyone have any thoughts? Anything I can do quickly to determine how bad it is?

Thanks in advance for any help!

bluesubie 05-10-2012 07:41 AM

The turbo oil line screen could also be clogged. Some of had luck by simply doing an oil change. Go with Rotella T6 5W-40 or one of the Mobil1 High Mileage oils (10W-30/10W-40) and do a short 1k mile interval. Subaru actually has a TSB that calls for using a Subaru branded flush (I believe it's the kerosene type flush) and I've heard cases of that working as well. http://www.scoobymods.com/showthread...ine-13825.html

Do you actually hear a tapping sound when the engine is running? Some actually get a tapping sound when the screens are clogged so it's probably a good sign if you don't hear any tapping.

-Dennis

BarManBean 05-10-2012 07:51 AM

If it were me I would just take it back. I don't believe that P0021 is usually nothing to worry about--you're probably looking at a new turbo soon, if not more. Hopefully others will chime in.

Mad Matt 05-10-2012 07:54 AM

Update: Reset it yesterday and it takes the third driving cycle to relight it.

I hear what seems to be the typical lifters tapping, sounds normal to me but I am not very familiar with the sound of the Subie engines. Where is the oil line screen? Is it easy to check like the banjos? Not sure if I am being paranoid now, but it idles a little rough under load (in drive), but I am used to a buttery smooth twin turbo I6 so I am not sure what I should expect from the H4.

BigTDogg (MA) 05-10-2012 08:22 AM

You're due for a timing belt job. Coincidence? Perhaps... or...

Get the warranty, or try to return it.

WTF has a TT I6? Poopra? 335?

2manysubies 05-10-2012 08:26 AM

+1 for BarManBean, P00021 is a "death code" Oil system, could be OCV sticking, same oil system that lubes turbo, also do a search on Banjo bolt screen filters, they are NOT EASY access items, I would bring the car back ASAP! Let THEM fix it!! Seems your starting the "Adventure"(new to 'you' car) with the worst possible indication. Just my 2 cents.

R/Mac

Mad Matt 05-10-2012 08:27 AM

Right, but isn't replacing the belt supposed to be preventative maintenance? Shouldn't it be running terrible if the timing is off?

Thanks for the responses.

BigTDogg (MA) 05-10-2012 08:33 AM

Quote:

Originally Posted by 2manysubies (Post 3888671)
+1 for BarManBean, P00021 is a "death code" Oil system, could be OCV sticking, same oil system that lubes turbo, also do a search on Banjo bolt screen filters, they are NOT EASY access items, I would bring the car back ASAP! Let THEM fix it!! Seems your starting the "Adventure"(new to 'you' car) with the worst possible indication. Just my 2 cents.

R/Mac

Quote:

Originally Posted by BarManBean (Post 3888601)
If it were me I would just take it back. I don't believe that P0021 is usually nothing to worry about--you're probably looking at a new turbo soon, if not more. Hopefully others will chime in.


You guys may know better than I do, but how does a P0021 relate to the oil system when it's a Cam Position code? Is it indicative of a AVCS failure?

thefultonhow 05-10-2012 08:48 AM

Quote:

Originally Posted by BigTDogg (MA) (Post 3888683)
You guys may know better than I do, but how does a P0021 relate to the oil system when it's a Cam Position code? Is it indicative of a AVCS failure?

Yes. The cam timing is over-advanced because of low oil pressure.

But, if it's just P0021, and not P0011 too, just replace the OCV on that side.

bmx045 05-10-2012 08:56 AM

The oil feed on the pass side head is 1 port, that 1 port branches to 2 lines, 1 line to avcs ocv, and 1 to turbo. the avcs ocv regulates the oil delivery to it to fill the cam up with oil making its rotational speed slightly slower thus "valve timing" adjustments. The cam position sensor detects this and equates a duty cycle to an expected cam position change.

no oil flow to it = no change in cam timing since no oil is filling and changing the cam speed (ever so slightly due to increased mass, our cams are almost completely hollow). when the ecu wants to advance the avcs intake timing, the ocv closes and reduces oil flow into the cam thus making its rotational speed slightly faster (^ timing). as the ecu's AVCS timing table calls for ocv open/closure, the ecu expects the cam position sensor to confirm this change.

the code 0021 and 0011 can come from either the avcs oil supply being restricted or the ocv solenoid itself is bad. if the code if for the passenger side, keep in mine the turbo is fed by the same line as the avcs, thus if it is infact oil restriction causing the code, the turbo integrity is at risk too.

Mad Matt 05-10-2012 09:13 AM

Are you saying that if I am just getting the one code (P0021) it is likely just the ocv? Which side is it (code reader says bank 2)? If it is on the driver side is the turbo safe?


The appeared to be no banjo filter on the driver side, but how far down can the filter fall if it comes out of the bolt? I looked down the hole but there was nothing shallower than say 1.5" down in the hole, could it be deeper than that?

Thanks again.

bmx045 05-10-2012 09:17 AM

if it's on the driverside the turbo is safe, yes. and if i recall correctly 0021 is drivers side. the banjo bolt on the drivers side goes from the avcs solenoid down to the front of the head- thats where the filter'ed banjo is, not at the solenoid. replace the solenoid and go from there, getting that banjo out behind the timing cover may be real tough

Mad Matt 05-10-2012 10:36 AM

Oh so I checked on top at the ocv, so that isn't where the banjo is, it is down on the front side of the head. So that could be my problem. Is that where it is on the pass side too?

Is anyone else sure of which side the P0021 (bank 2) refers to? Where is the oil line screen that bluesubie mentioned?

Thanks again.

bluesubie 05-10-2012 10:41 AM

http://legacygt.com/forums/showthrea...val-61689.html

bmx045 05-10-2012 10:44 AM

let's step back for a second. banjo bolts are what you see, the banjo bolts with a nipple on them have a filter in them. the banjo ontop of the solenoid does not have a filter in it, follow the oil line down to the head- that banjo has a filter in it. on the pass side your banjo bolt (with filter) is directly underneath the turbo on the back side of the head. that one feeds the turbo and avcs solenoid oil. it's 1 line that hits all 3 places- feed banjo bolt to turbo and to avcs. thats why i said if that banjo clogs it restrict oil to the avcs solenoid (thus p0011) and turbo


All times are GMT -6. The time now is 08:49 PM.


LegacyGT.com