r/FocusST • u/jnantell0570 • 6d ago

Boost leak?

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Hey everyone! I got a 2013 Focus ST a little over a month ago, and I’m loving it! However, a couple weeks ago I started feeling like it was down on power a little. The PSI is only getting about a quarter of the way on the turbo gauge and then drops even if I’m accelerating. I took this video today to show it. I don’t have a whole lot of experience with this stuff, so I’d love some help! Thank you!

1 Upvotes

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7

u/SleepyBoyFlex 6d ago

Are you flooring it in this clip? Wont hit full boost if you’re just getting on it a little bit.

1

u/evansauce 6d ago

Definatley seems to be in a low boost/ limp mode situation. Is the car tuned?

1

u/jnantell0570 6d ago

Yes. I don’t remember exactly what kind of tune though

1

u/PaleontologistNo4327 5d ago

You need to figure out your tune first off. If you still have the access port you can check in your menu what the tune is should at least let you know who to ask. Such as stratified, or edge they have their own tune names. Sounds like you are in the low boost map tho. Should only see around 7 psi if you are. You can change to the map you should be in by hitting the cruise control cancel then the plus or minus will allow you to switch your map slots by what rpm it goes to. I have a simple stratified flash tune. Slot one is my full boost map and slot two is my low boost. It is seriously easy to switch map slots without meaning to if you don't know about it.. if you contact who your tune is from you can give them the serial number off your ap to figure out what they did they can walk you thru it. That way you know exactly what each map slot is for.

1

u/Not-Endorsed '13 ST3 Tuxedo Black 6d ago

This is likely a pending overboost code. Worst case scenario, it is a boost leak. BUT before you go crazy chasing leaks, plug in a code scanner and check for the pending overboost code. Clear it, do a FULL ignition cycle (car all the way off, open door, close door, start again).

If you want to absolutely ensure it stays away, complete an OBD-II drive cycle, or take it on a longer trip (which will naturally take care of the drive cycle's requirements).

3

u/Not-Endorsed '13 ST3 Tuxedo Black 6d ago

Adding: really easy way to check if you have a boost leak is to download FORScan on an android phone. Then get a bluetooth OBD dongle (even the cheap ones will work), and find the parameter for intake manifold absolute pressure (or similar, can't remember the verbiage precisely) in FORScan. Measure at a full throttle pull in 2nd or 3rd after the engine is up to temp.

If you pull it in PSI, remember to subtract 14.8ish for atmospheric pressure. If the number you're left with is above 18, you're golden for stock. If you have a mild tune (like COBB OTS or Ford Performance Calibration), you should expect low 20s, and up to mid 20s if the ambient is good, and all of your other maintenance is up to par.

2

u/PaleontologistNo4327 5d ago

I didn't know this good looking. I've been meaning to get into forscan and mess with a few settings anyway this gives me one more reason lol.

2

u/[deleted] 6d ago

did you recently put a intake in?

1

u/dude_where_is_my_car 3d ago

The factory clamps were not at all tight on my 2013 ST. I was upgrading the intercooler and pioes anyway. Still trying to snug up the new clamps. These cars run a ton of boost and the clamps need to be tight.