Lost power while accelerating on hwy

Sorry if there's any formatting issues- I'm typing on my phone at the moment.

 

Car is ots stage 2, ip&t line, cobb dp, spt v2 cbe, stock ic and intake, making roughly 18.9psi according to AZP.

 

So, while driving down to Philly international to catch a flight, I was cruising in 5th around 80mph and decided to open it up just a little more. I was probably at 4.5k rpm (maybe less) when allsof a sudden,a huge pop/bang happens and power cuts off entirely. Pop into neutral and coast gently to the shoulder o f the highway. Check engine light, oil, and battery lights come on - cruise control light and si-drive symbols are blinking. Pop open the hood, no smoke, no visible leaks, and no smell that i can detect. Can't really hear any issues due to the SpT.

 

I didn't have my AP on me, so I couldn't run any diagnostics, unfortunately. I was able to turn the car over and drive it to my friends house, going easy on the gas (never exceeding 3k rpm) , even with all the lights on.

 

So basically, what could have happened?? Is the car still "driveable"? Could I just reflash the stage 2 map and cheese the lights? Or am I doing irreparable damage to the car by driving it any more? The earliest I can take the car to AZP is next Friday...

 

Any advice, words of wisdom, or help? This had never happened before, so I'm a bit concerned. Thanks in advance.

Sounds like you blew off a vacuum line. Check the blue t fitting under the intercooler. Get the codes.

Sounds similar to what my car did right after I flashed the OTS Cobb stage II tune. The car over-boosted and cut power with a bang. I used the AP to reset it. At the time, there were two versions of the stage II map with different wastegate duty cycles to control over-boosting, I switched to the other and was good to go.

Once you're back from your flight, pull the code and post it here, otherwise we're kind of shooting in the dark.

 

I got an overboost code, P0244 while still 100% stock. When overboost happens, fuel is cut off as a safety measure - that's your loss of power. It scared the shit out of me, being the first (and only, so far, knock on wood) CEL I've had with the car. Here's my thread:

 

http://legacygt.com/forums/showthread.php/p0244-need-help-part-number-210023.html?t=210023&highlight=p0244

 

For me, one of the lines coming off the T broke. You may have blown the line off, or broken it. Or something entirely different may be broken.

 

Easy fix, in my case.

Thanks for the reply, guys. I'm still a bit concerned, but less so now. I'll just have to stay off the boost when I drive it back home, and I'll check the hoses + code and give an update. I guess this is more reason to keep the AP in my trunk from now on.

 

@Dbl - what's the name of the other Stg 2 map, and did it affect your boost levels negatively in any way {delay, hesitation, lower peak etc)?

 

Much appreciated, guys.

If you follow this link, you'll see the list of OTS maps from Cobb. I started with the "normal wastegate" stage II map and overboosted within a few minutes of driving, so I reflashed with the "low wastegate" map and didn't have a problem with it again.

 

http://www.cobbtuning.com/Accessport-Off-The-Shelf-Maps-s/40100.htm#/v/accessport/maps/subaru/lgt/LGT-Maps-08-09-Stock-Intake

Update: Looks like I overboosted - P0244 Turbocharger wastegate solenoid 'A' Range/Performance.

 

Haven't had a chance to check the hoses/under the hood since I got back at 3AM this morning in freezing ice rain/slush. But this morning, I cleared the code, reflashed OTS Stg2 91oct (didn't have a chance to download the low wastegate map just yet), and drove to work without issues.

 

I drove gently, but did a few moderate pulls in 4th just to check what levels of boost I was hitting - 18.1psi without pushing the car (AZP measured 18.9 after putting in my Cobb DP). My question is: If, hypothetically, a vacuum line blew off, a hose was busted, or the WG wasn't functioning correctly, would I have been able to achieve that 18.1?

 

Thanks for the help, everyone. I'll most likely flash the low wastegate OTS stg2 map, but want to narrow down the problematic areas.

If you blew off a vac hose you would probably notice. How is your idle? How much vacuum are you pulling? Have you checked/logged AF correction values?

 

Likely, you just hit fuel cut from overboosting (likely due to cold air and high load/high gear). Feels like hitting a brick wall, doesn't it

Sounds like a simple over boost with the cold temperatures. Clear the code, flash the low wastegate 91 stage 2 map, and you should be good to go.

if you still have the stock MAP sensor, 2.5 bar ABS, then you were out of that sensors range.

Thanks for all the input, guys. Spoke with AZP and they agreed that it was likely just an overboost/cold temp issue. Might go in for a smoke test to check for any leaks, but they recommended keeping the same map + keeping the AP in the car to avoid any future heart attacks.

 

Idle is smooth, without hesitation or stuttering. If I recall correctly, the low/high from my morning commute was -11.5(ish?)/+18.1 psi. I have not checked A/F Correction, but was reading up on it earlier today since I've never looked at that value before and don't quite understand its meaning.

 

And yes, it was a solid brick wall. Good thing I'd packed extra boxers for the trip, cause that wasn't cool.

 

I'll probably run a data log on the commute home tonight.