Vehicle: 04 FXT 4eat

Got stock boost gauge and only getting .07mpa or about 11psi in stageII. Did a live boost reading in the AP and verifies only 11psi tops.

And only .05mpa in StageI.

Mods: sti upipe/manifold, TXS stealthback.

Looked/listened for any boost or vacuum leaks.. seems ok. Like I said, before the mods I was only getting .05 for stageI and should be like 13psi.
No codes were listed in the AP. Any thoughts for troubleshooting?
I was looking at a TDC etune or "road" protune? Would that fix it??

Tried resetting the ECU through the AP so far too.

 

Is the exhaust manifold much larger (ID) than the oe manifold?

Did you have the oe manifold with stage 1?

Are you hitting target boost after a reset then it gradually goes back to 11psi?

 

I think that the sti exhaust manifold and fxt manifold are close size wise, just supposed to flow a little better..

did not have it for stage 1.. only getting .05mpa for stage I

 

Are you hitting target boost after you reset the ecu then it gradually goes back down to 11psi or is it low after a reset also?

 

Nope.. I hit 11psi and it's like it "says good enough"

 

you have to give the ECU time to learn. Resetting the ECU will only make this take longer because it resets any learned information that allows the car to safely reach peak boost. Give the car about a week or so and see if youre hitting target boost then

 

If you've given it enough time to learn and your still not hitting target boost Cobb has high wastegate maps that might help. I'm not familiar with the FXT's but if the wastegate arm is adjustable that might be something to look into also http://www.scoobymods.com/forums/showthread.php?t=3654 . Some say that this adjustment wont help with low boost but it seemed to do the trick on my 02 stage 2 WRX when I was having low boost problems.

Another thing to look into is the restrictor pill. If your turbo vac lines have been manipulated it may be missing or in backwards. I have no experience with restrictor pill problems and I'm not 100% positive it will cause low boost but I think I remember reading something about it and low boost.

 

Can anyone with data log experience, give me some advice as to what is going on with my car?? Only getting 11psi, instead of 13.5psi per cobb's site.

04 forester XT (2.5 turbo)
mods: sti scoop/exhaust manifold/up pipe/cobb stageII/TXS stealhback

I have attached two .csv files from EcuExplorer in zip format

thanks, john

 

Do you have a downpipe? If not you need one for stgII. ( Not familiar with the TXS stealthback system) Also try running the high waste gate map.

*** Be sure to use the right AC adapter or you'll fry your AP. ***

 

Yes, TXS stealthback has 4" DP included". I called Cobb and spoke with Chris over there.. Got a few things to check.. Frome what I've been told.. They didn't have a high wastegate map for my car.

 

Here's what I've tried up to date:

• Checked & Re-checked IC piping, Y-pipe and to TB (no visible cracks)
• Verified Restrictor pill installed
• Uninstalled and Re-installed AP
• Flashed base Map to ver. 111
• Checked Up-pipe to manifold connection
• gave wastegate arm end two turns -- (helped a little)
• Generally looked/listened for any vacuum leaks

Car runs well, but just doesn't get anywhere near target boost (15psi) per Chris at Cobb

 

i had this problem with my 04 wrx. i just installed a boost controller. that did the trick. did you buy the car like this? or did you do all the mods after you bought it?

 

When I was referring to vacuum leaks I was talking about the vac lines that run from the Factory boost controll solenoid (FBC), wastegate, T and turbo outlet. sounds like you looked that stuff over when you checked the restrictor pill though.

How much did it help? If you haven't seen any boost spike you might want to keep turning until you see a spike and then back it off a bit until the spike is gone.

Do you know any people in your area with a FXT that might be willing to swap FBC's for a test run?