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ScoobySnax 10-04-2012 08:52 PM

AccessPORT low boosting
So I have a 2005 Legacy GT with an SPT intake and Cobb AP. Every once in a while the boost drops and it runs sluggish. Now I started to monitor the boost and it was 8.8lbs tonight. Now it will usually go back to normal when I reflash it but I dont feel I should be having to reflash every week.

Does anyone have any idea or any experience with this.

Sorry if it has been posted before, I have been searching for the past 30min today and many times in the past.

Oh yea, I got the AP back in May 2012 and this started happening around late Aug 2012

chaz517 10-04-2012 08:55 PM

Does limp mode kill boost like this? That could be it

ScoobySnax 10-04-2012 08:58 PM

what is limp mode

Nrw 10-04-2012 08:59 PM

boost leak test

ScoobySnax 10-04-2012 09:02 PM

I dont think its a boost leak because it goes back to normal when I reflash it again

chaz517 10-04-2012 09:12 PM

Limp mode is pretty much when the car senses something isnt running right and reduces power to prevent damage. Flashing the ecu every week to fix it probably is not a good idea, but again not sure if thats what is going on w ur car right now. Check all your hoses just so u can cross that off ur list

EJ25subie05 10-04-2012 09:15 PM

sounds like a boost leak to me. are you tuned for that intake? my intake caused me more problems then i knew what to do with and took it off and set it on my table ever since. waiting for a pro tune

ScoobySnax 10-04-2012 09:35 PM

hmm, do you think I should divorce the AP to see if it helps until I get it pro tuned

EJ25subie05 10-04-2012 09:41 PM

you didn't say anything about a dp or anything so I'm assuming your only on stage 1? put your stock intake back on, and if the mods you have allow you to go back to stock then divorce the AP and see if the problem still occurs. are you using your AP to monitor boost or a gauge?

ScoobySnax 10-04-2012 09:53 PM

yea, just stage 1 for now. I was using the boost controller on the AP. I think im gonna take your advice and go back to completely stock tomorrow. I hope it works.

Do you think I should reflash to correct it then divorce it???

cryo 10-04-2012 11:00 PM

Normally the ap alone should not cause these issues. It may be something mechanical causing the ignition advance multiplier to drop thus wastegate boost.

Pull up your live monitors and look at dynamic advance multiplier or DAM while you are seeing the 8.8 psi issue. Is it less than 1.0?

Its hard to say without some logs but stg 1 is normally pretty strait forward.


Berzerklo 10-05-2012 11:46 AM

Those SPT intakes are notorious for messing with your MAF readings.

ScoobySnax 10-05-2012 03:39 PM

I took off the AP for now and putting the stock intake back on this weekend. If everything goes well then Im gonna try the AP again in 2 weeks. I hope I will have good news by then.

Thanks Dave, Im gonna post the data when I try again in 2 weeks cuz I didnt see your post before I took it out.

I really appreciate all the quick responses. This is my first Subaru and first time using forums for help. The Subie family is really a great family.

cryo 10-08-2012 02:19 PM

There are great members on this forum, its the best online community i have had the pleasure of being a part of.

Keep us updated.


cryo 10-17-2012 09:09 PM

Any updates?


ScoobySnax 10-19-2012 02:30 PM

So I have had the AP off for 2 weeks and no issues. I had to work all last weekend and weather was kinda shitty with no garage the first weekend. Hope to put my stock intake back on this weekend while hooking the AP back up.

iNVAR 10-20-2012 07:36 AM

as a previous poster said, check the dam. if your dam is dropping, find out what the reason is. do not reflash. that is 1) unnecessary. an ecu reset does the same thing 2) masking the problem that the dam drop is trying to help with. your car is likely pulling timing for some reason and that's why dam is dropping.

robinlsb 10-20-2012 10:12 AM

The SPT intake is a POS. It runs hotter than the stock air box, screws up the MAF, and god knows what else.

Cobb did a comparison test between the stock box and the SPT. Look it up on Cobb's web site. The SPT was worse than stock in all areas.

Hot intake air will reduce boost and timing to prevent detonation. I suspect that is your problem.

YourConfused 10-20-2012 10:57 AM

I am not even close to knowing as much about tuning parameters as Dave, but I do know that the SPT intake is not a good design. It induces turbulence at the MAF which causes irregular readings AFIK. Also, as I understand it, COBB does not have their stage 1 or 2 maps tuned for a aftermarket intake of any sort.

I may be wrong about anything I stated above, so just look into what I said and see for yourself if you find any truth in it. As far as a boost leak goes, well who knows? It may be so or not, but in either case you could benefit yourself by looking for a leak and as a byproduct, familiarize yourself with the motor's induction side. It could be a win/win.

You gotta start the learning process some where, so just pick something, learn it, and move on. This way you will get to know your car and also eliminate variables in the process. Good luck with it all.

ScoobySnax 10-26-2012 02:22 PM

Forgive me for my ignorance, but what is a dam? I took off the intake today and married the AP again. I put about 75 miles on it just driving around and so far so good. Some people have asked me to log some of my data but not exactly sure how to or which data to log exactly. There are so many options on the AP.

Flipapotimus 10-26-2012 02:35 PM


Originally Posted by ScoobySnax (Post 4131944)
Forgive me for my ignorance, but what is a dam? I took off the intake today and married the AP again. I put about 75 miles on it just driving around and so far so good. Some people have asked me to log some of my data but not exactly sure how to or which data to log exactly. There are so many options on the AP.

COBB video on Data Logging here

Also here is the COBB link to other tutorial videos about the AP, they are at the bottom of the page.

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