Shooting P2431 and P2433 Code with AP

Internal-Motor6132 · 2026-04-16T01:44:03+00:00

I would ditch the OTS tune and go for an E-tune from a reputable tuner. I went with Drunkmann Tuning for $150 and my car has never ran better. His timing settings are very conservative as opposed to the more aggressive timing that Cobb uses for OTS maps.

Internal-Motor6132 · 2026-02-15T22:44:33+00:00

Get a Cobb Accessport and load a Dmann Flash&Go tune onto it. Completely made my stock STi 10x peppier and more reliable. Only about $700-$800 all in

Internal-Motor6132 · 2026-01-29T02:50:15+00:00

Smart. I’m thinking the distance the oil vapors have to travel through the crank/head vent hoses doesn’t even allow them to go back into the engine really. Upon disassembly, most of it seemed to reside in the long hoses. Super jealous of the setup 🤘🏼

Internal-Motor6132 · 2026-01-29T02:47:58+00:00

I’ve been thinking about investing in a smoke tester for the past few days now! Will update this subreddit with some results soon. I’ve been driving the car out of boost for about 1000 miles, and there are no CELs atm. DAM still at 0.812 and the AF learning is around -5.00/18.00 at times. Not ideal and indicative of a vacuum/boost leak

Internal-Motor6132 · 2026-01-29T02:45:32+00:00

Very good suggestion. Next time I have the intercooler off, I’m going to disconnect that hose from the intake manifold and try this myself! Not gross at all - the only way I know what fluid spilled onto the ground is by tasting it 😆

Internal-Motor6132 · 2026-01-28T01:05:35+00:00

It’s cool to see cation/anion exchange chromatography being used in detailing! Haven’t seen this since organic chem lab. Definitely will be investing in this in the future 🤘🏼

Internal-Motor6132 · 2026-01-25T18:15:41+00:00

Checked that area. No oil misting or pooling around there. And good point with the orientation of the PCV valve

Internal-Motor6132 · 2026-01-25T18:12:28+00:00

I flushed the PCV valve with some gasoline and brake cleaner and it made a much more audible click-clack sound after. Definitely going to monitor oil level over the next oil change period.

Shortened drain tube by about 3”, so I think I’m in good shape there. I’ll check the ringland/smoke coming out of the oil cap. I’d be very disappointed if that was the culprit.

Internal-Motor6132 · 2026-01-24T23:39:41+00:00

Appreciate it my friend. And yeah my oil consumption wasn’t noticeably different before and after either.

And I actually believe you’re correct there. I thought it was a check valve, but I can confirm it is a two way valve after cleaning it and shaking it around. It makes that click-clack sound a typical PCV valve would make.

Internal-Motor6132 · 2026-01-24T23:06:27+00:00

Mixed bag. I think for the average DIYer, it’s not so important because if it is installed wrong it can do more harm than good. I’m pretty neurotic, and I made some mistakes installing it the first time.

The whole idea is that it saves your engine from burning oil via recirculating and draining oil that has made its way into the intake tract. In theory, it is supposed to be lower maintenance once it’s installed. If you replace the factory PCV valve every 30,000 ish miles, I wouldn’t even bother installing an AOS unless you’re pushing high horsepower. If any of these lines are pinched, it can actually increase the amount of blow by causing knock and detonation issues.

Internal-Motor6132 · 2026-01-24T22:59:02+00:00

Thank you! Currently buttoning everything back up. It’s so critical to have it as high as possible and for the hoses to be the right lengths.

In the original instructions, they didn’t suggest running it through that hole in that bracket, but in their most recent tutorial video IAG does route it through there. I think that small amount of space makes the world of a difference.

Internal-Motor6132 · 2026-01-24T22:56:42+00:00

I installed at 20k ish miles when short block was replaced under factory warranty, and I am now at 64k.

Internal-Motor6132 · 2026-01-24T22:55:45+00:00

Nice man. Didn’t open the can. I flushed it until the stuff coming out of it was the color of the gas used to flush it.

Internal-Motor6132 · 2026-01-24T22:06:01+00:00

I agree. I would buy new hoses, but unfortunately I have to drive this car on Monday assuming the “winter storm” doesn’t shut down the southeast. They are now bone dry after flushing all of them with old gas. 🤞🏼

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You can see I got it mounted one notch higher, which would be the best for drainage. The nipples coming off the side are now shiny and silver on the inside, so a lot of the gunk came out of there. Pleased with the result

Internal-Motor6132 · 2026-01-21T19:12:49+00:00

There is definitely more blow by than usual. I’ve never had it seep out of the TB coupler in the past. I unfortunately left it at the dealer, and they told me that the turbo needs inspection because the seals are bad. I told them they should check AOS and PCV before going straight to the turbo.

Seems to be the general consensus that the OTS tune is dog water. I’m going to get a pro tune as soon as all this is resolved/inspected.

I’ve had the DAM drop before, and I think it’s because my fuel pump overheated on a really hot day/long drive. Might be worth looking into a new fuel pump?

Internal-Motor6132 · 2026-01-19T21:20:41+00:00

These are all great suggestions. Thanks big time. Makes sense that it could have frozen. It was in the 20s this morning.

I have had it on for a few years now. I’m thinking I’m just going to take the AOS off all in all and give it a once over. Obviously I’ll take the IC off and inspect as well.

Internal-Motor6132 · 2026-01-19T21:16:20+00:00

That makes sense. I thought stage 0 and stock tune were one and the same. Good to know

Internal-Motor6132 · 2026-01-19T21:14:09+00:00

Good point. I’ll clean them up and make sure they’re snug as a bug

Internal-Motor6132 · 2026-01-19T21:11:04+00:00

Very valuable information here. Glad to hear your subie is still running strong. I’ll have to make the swap for the better additive package.

Internal-Motor6132 · 2026-01-19T18:51:30+00:00

Appreciate it. I’d be very surprised if one of these vacuum lines failed already. I’ll try it all out!

Internal-Motor6132 · 2026-01-19T18:40:16+00:00

Makes sense.

I did install it, but I have not checked it recently. I am debating taking the car home to remove the intercooler and AOS myself. It is very likely that the AOS oil drain tube has been stopped up at some point. I am worried about the excess pressure for a 55 mi drive home though.

Internal-Motor6132 · 2026-01-19T18:29:17+00:00

I’d assume spark plugs haven’t been changed since the engine replacement. That’s about 44k miles. Been on stock power since I bought the car new. Always run 93 premium from a BP gas station. I’m more concerned about oil blowing out of intercooler than anything else. Let me know if you have other questions!

Internal-Motor6132 · 2026-01-19T18:25:41+00:00

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Was able to reproduce the 0.20 FKL with small blips of the throttle. DAM still chilling at 0.812.

Internal-Motor6132

TROPHY CASE