‘05 OBXT needs tuning help

[RumblyXT]

Hello everyone!

I recently purchased an '05 Outback XT, my first ever turbo Subaru.

The car came with a few mods: (AEM CAI, unknows Down Pipe, JRTuned Intercooler, Grimmspeed EBCS and a turbo to AVCS custom routed oil line), but no Access Port..

 

The previous owner was a mechanic who maintained the car for a year, changing breaks, fluids, suspension components, etc. until I purchased the car.

Rumbly currently has 210K miles and I honestly have no idea what tune it has, and/or if there's an AP married to it or not.. already trying to contact previous owner before the mechanic.

I'm getting really bad mileage with it (about 13.5-14mpg)..

 

I really like the car and I'm very excited to finally own my very first turbo Subaru, but I obviously should have done more research before jumping into a modified car without its AP.

 

My plans are to eventually overhaul the engine(replacing its seals, gaskets, grommets, etc)..

 

What do you guys suggest I do in terms of the tune issue?

I want to purchase an aftermarket CB exhaust but I don't want to do something wrong and end up with a blown motor..

 

Your help and suggestions will be greatly appreciated.

Edited December 17, 2021 by RumblyXT

[dwmccauley01]

You can get an openport 2.0 or cheap vagcom cable to log and reflash. There's a few good writeup on how to get that set up.

 

https://legacygt.com/forums/showthread.php/using-autonostics-vag-com-cable-read-flash-ecus-110768.html

 

https://legacygt.com/forums/showthread.php/complete-beginners-guide-e-tuning-vendor-and-vag-com-cable-158118.html

 

Hopefully he has a tune, these cars don't usually respond well to modding without a tune. Once you get a cable and pull a learning view it may be easier to see what's going on.

 

Also if you're burning oil, at that mileage it may be more worthwhile to get a shortblock as the piston rings are likely worn and the cylinders like to round out over time.

[RumblyXT]

I got so excited when I saw an OBXT was available around me, I didn't research into it further not knowing that any mods on a Subaru require a tune.. these cars are very hard to come by, especially one with no rust on the undercarriage.

 

Bringing the car back to stock would probably cost me more money that I don't have now, so that's out of the question. Hopefully I can get in touch with the previous, previous owner so he can point me in the right direction.

 

I've only had the car for a month, can't really tell if it has been burning oil, but I don't think so. I actually just replaced the engine oil today with Valvoline Synthetic 10W-30 and a Wix XP filter.

 

And then on top of that, while I was inspecting the car under, I found pressure pliers clamping the heater bypass hose (talk about a hack job) that goes behind block to the cabin, I'm guessing to the blower..

 

I really know very little about tuning.. I'm trying to learn/understand now what I need to do. Thank you much for your help and links, I will check them out.

[whitexc]

Keep an eye on the oil level for a bit. As in check it every other tank of fuel or so until you know it's habits. Low or even at the add mark is asking for problems. Keep it topped off.

 

As for the heater hose clampage...that is worrisome to me. Does the car have heat? Does it smell like antifreeze in the cabin? The heater core may be bad and they knew it. Some older cars (think Ford) had a restrictor in the heater hose....maybe this is what they were trying to accomplish but was mainly necessary when running high volume water pumps.

 

Tuning can be done in various ways. If the car has no AP, is it not likely tuned via Opensource through a protune or other cable based flash? Asking for others much more savy than myself to chime in here. I came from Fox Fords so.....

 

How does it run in its current state? Any dash lights?

 

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Edited December 18, 2021 by whitexc

[RumblyXT]

I have a feeling the heater core went bad and/or there was leaking inside the cabin, hence they clamped the engine block to heater core hose to prevent spillage inside (I just wished they had done it the right way instead of such a hack job).

 

I can always try doing a heater bypass from the back of the block back to it until I figure the issue with tuning first. Living in Miami we don't really need the heater most of the year thankfully.

 

I haven't tried using the heater to see if it smells and/or leaks inside the car and now I want to do it even less.. haha

 

A/C blows super cold though..

 

Car actually feels pretty good for its mileage and it seems to run smooth, no rough idle or weird noises. No CEL lights either, but they might have hidden those with the tune since I have a CAI, aftermarket Intercooler and a catless down pipe.

 

If I cannot get a hold of the person that previously had the car tuned, I'm going to have to do a whole lot of reading and learn it myself. Might be beneficial after all to really understand how everything works..

Edited December 18, 2021 by RumblyXT

[RumblyXT]

I almost forgot, is the coolant temperature gauge supposed to go a bit above operating temperature if the car is driven a little hard for a few minutes(like stepping on the gas hard on a straight long road)? I have noticed that a few times..

[dwmccauley01]

I have a feeling the heater core went bad and/or there was leaking inside the cabin, hence they clamped the engine block to heater core hose to prevent spillage inside (I just wished they had done it the right way instead of such a hack job).

 

I can always try doing a heater bypass from the back of the block back to it until I figure the issue with tuning first. Living in Miami we don't really need the heater most of the year thankfully.

 

I haven't tried using the heater to see if it smells and/or leaks inside the car and now I want to do it even less.. haha

 

A/C blows super cold though..

 

Car actually feels pretty good for its mileage and it seems to run smooth, no rough idle or weird noises. No CEL lights either, but they might have hidden those with the tune since I have a CAI, aftermarket Intercooler and a catless down pipe.

 

If I cannot get a hold of the person that previously had the car tuned, I'm going to have to do a whole lot of reading and learn it myself. Might be beneficial after all to really understand how everything works..

If it's catless without codes it definitely has some sort of tune. I'm not sure how it would work if it's married to an ap, I'm not sure if you can reflash it or not. But if it was open-source it's super easy to pull the flash to see what was changed in the tune. Thankfully, there's a tone of resources related to subaru tuning so I would just search up subaru tuning guides or on romraider.com to get more information. It's a bit intimidating at first but once you get your stuff set up and understand the basics, it's not bad at all.

 

I would recommend getting a general VAG-COM KKL 409.1 cable from Amazon or elsewhere to start or go ahead with a openport 2.0 but they are a bit pricey. Either way since it's tuned there's no easy way to tell what's going on without logging some data on it

 

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Edited December 18, 2021 by dwmccauley01

[dwmccauley01]

I almost forgot, is the coolant temperature gauge supposed to go a bit above operating temperature if the car is driven a little hard for a few minutes(like stepping on the gas hard on a straight long road)? I have noticed that a few times..

I have never noticed my coolant temp go above halfway, may be something to keep an eye on. I redid all the timing components and thermostat not that long ago so that may affect it.

 

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[Max Capacity]

For the coolant temp issue, replace both radiator caps, they are cheap and may fix your issue. I recently replaced both mine in the 05.

 

You can links to Tuners in the threads below this one if you need.

[RumblyXT]

Just replaced the oil cooler water pipe today, it was all rusted and pitted. Also flushed the coolant as well, even opened the drain plug at the bottom of the motor. Then replaced it with Subaru 50/50 along with Water Wetter.

Not sure if that might help with the slight overheating though. I have a feeling something else is going on. At least I know the car has the best coolant it’s supposed to get.

Go OEM or go home!

[Max Capacity]

You should burp the coolant system, raise the right front corner as high as you can, remove the cap from the turbo tank, start engine, turn heater to hot, watch for bubbles in the tank, add a little coolant as needed, but don't fill it to full.

 

Carry coolant in the car for a couple of day's and top off the overflow bottle as needed.

 

I've used Preston coolant for over 15 years now.

 

You shouldn't need water wetter.

 

I have a NAPA turbo tank cap.

[RumblyXT]

Thank you Max Capacity, I've heard of your engine build thread, I have to check that out! I will replace both rad caps as well.. you give me hope on my 210K mile car.

 

I did burp the system at the turbo/engine coolant filler tank with the big yellow funnel looking for bubbles coming out of the system while revving it slowly up to 2K rpm (I wanted to turn on the heater to make the process faster, but some intelligent person left a pressure clamp on the heater core line to the cabin).. I'm guessing it's probably leaking inside.

 

The car was on jacks all 4 wheels.. I left the engine running for 15 minutes. The next day, I had to top off the reservoir tank, it was very low, but the job went great, no coolant leaks anywhere.

Edited December 24, 2021 by RumblyXT

[RumblyXT]

I guess to really find out what's going on with the heating issue, I'd have to remove the whole dash to be able to see if the heater core is damaged, clogged and/or leaking.

 

I also hear the subtle cracking/popping sound of a door vent actuator right in front and a bit to the right of me when I'm driving, maybe it's also related to why they clamped the coolant inlet hose to the heater core.

[Max Capacity]

If your going to pull the dash out, you may want to start a new thread in the 4th Gen forum or read the related Interior Forum below.

 

A lot of us never get down this far in the forum and seem to get stuck in the 4th Gen forum.

 

There are a number of guys here who have removed the dash or had issues your talking about. You'll get more help in the 4th Gen forum.

[RumblyXT]

Thank you MaxCapacity..

Yes, I was thinking on doing that since this one falls under Tuning.