2005 Legacy Turbo GT Long Crank but starts fine with my foot on the accelerator

[05LGT25]

Like the title says, I have an intermittent long crank. I'm talking like 10 seconds of cranking. Seems to happen more after sitting for awhile. Sometimes it starts fine though. But when the long crank occurs, as soon as I put my foot on the throttle while still cranking, starts right up and runs fine. Every single time it acts up, foot on the accelerator starts it right away. My first assumption was rich condition or fuel injector leaking into the cylinder, so the extra air is correcting the mixture. But from what I've read online, the throttle body is electronic with no cable. So does the foot on the accelerator pedal even open the throttle when engine isn't running? I've only had this car about two weeks. It's my third Subaru but it's been about 15 years since my last one. Car has been modified. Has full 3 inch exhaust, intake, FMIC, TGV deletes, and probably more I don't know about. Dyno sheet was 370hp so I assume it's got some kind of tune. I was told turbo is OEM. Has a new battery and runs great otherwise. 

I'm a mechanic. My first step is going to be fuel pressure testing and bleed off, but I figured before I start diaging this thing, I was hoping there may be something common that people here on the forum may recommend looking at first. I looked around online and couldn't find much. 

Thank you ahead of time for any help or suggestions.

Edited May 4, 2023 by 05LGT25

[Pleides]

Still on sidefeed injectors? They might need replacing.

[05LGT25]

4 hours ago, Pleides said:

Still on sidefeed injectors? They might need replacing.

I think so. Fuel rails, etc all look OEM. Injector tops that are visible are yellow and don't look recently replaced.

[Infosecdad]

If it dynoed at 370hp with stock injectors, they are being pushed beyond their limits. 

I don't think I've heard of the stock injectors making over 320-330hp (crank), so I can only imagine their duty cycles are maxed out.

How many psi of boost?  370hp will be really hard on stock/oem turbo and fueling.

[KZJonny]

Can a VF40 get to 370hp regardless of psi?

I was distinctly under the impression it would not. I was told to expect under 300 with my JMP and a good tune with mods….

Sounds like a questionable dyno sheet, or non-stock turbo. Or perhaps it is OEM, but not a VF40? Can a VF52 get you up to those numbers?

[05LGT25]

22 minutes ago, Infosecdad said:

If it dynoed at 370hp with stock injectors, they are being pushed beyond their limits. 

I don't think I've heard of the stock injectors making over 320-330hp (crank), so I can only imagine their duty cycles are maxed out.

How many psi of boost?  370hp will be really hard on stock/oem turbo and fueling.

 

4 minutes ago, KZJonny said:

Can a VF40 get to 370hp regardless of psi?

I was distinctly under the impression it would not. I was told to expect under 300 with my JMP and a good tune with mods….

Sounds like a questionable dyno sheet, or non-stock turbo. Or perhaps it is OEM, but not a VF40? Can a VF52 get you up to those numbers?

I appreciate you guys taking the time to reply. Dyno sheet doesn't appear to show boost. I also have no boost gauge, it only has a MAC solenoid plumbed in. I have no idea on the turbo. The guy I bought it from had own several Subarus and said turbo was stock. The only markings I can find on it is one spot on the front of the compressor housing that is stamped 21501 .

Is there any way to tell if injectors are factory without removing them? 

I've attached some pictures of the turbo, injectors, and dyno sheet. 

[KZJonny]

Those are stock yellow-top sidefeed injectors. Doesn't mean they haven't been *f*'ed with tho. Not that that would be a bad thing, necassarily, just that there are ways to increase flow through them.

That is not a VF40. Again, not that it matters, and perhaps the previous owner forgot that he did something with it, or some such. Could still be an OE turbo, but I only really know what mine looks like, and that is not quite it....

Commentary above is correct tho, and you're on the bleeding edge of what the fuel system is capable of supporting, probably beyond it. Welcome to the site and all of that.
When you're done all your diagnostic work, you'll probably have a better idea what you're working with... For reference, you should see about ~40-42 psi on the fuel system without vacuum reference. I wonder if maybe your car is running higher pressure to get more fuel through those little side feeds?

I think if it were me, I would go easy on it until the general health of all that could be baselined. If the injectors are tiring out, I doubt you've got much, if any, room for error in that tune before you lean out.

[05LGT25]

Just now, KZJonny said:

Those are stock yellow-top sidefeed injectors. Doesn't mean they haven't been *f*'ed with tho. Not that that would be a bad thing, necassarily, just that there are ways to increase flow through them.

That is not a VF40. Again, not that it matters, and perhaps the previous owner forgot that he did something with it, or some such. Could still be an OE turbo, but I only really know what mine looks like, and that is not quite it....

Commentary above is correct tho, and you're on the bleeding edge of what the fuel system is capable of supporting, probably beyond it. Welcome to the site and all of that.
When you're done all your diagnostic work, you'll probably have a better idea what you're working with... For reference, you should see about ~40-42 psi on the fuel system without vacuum reference. I wonder if maybe your car is running higher pressure to get more fuel through those little side feeds?

I think if it were me, I would go easy on it until the general health of all that could be baselined. If the injectors are tiring out, I doubt you've got much, if any, room for error in that tune before you lean out.

Thanks for the reply. That all makes sense. Fuel pressure test is my next step. If that's good, I'll likely take it to a tuner to give it a thorough checkout and go from there. 

Also, just looking around online at oem turbos (hoping to match up my serial number markings), the OEM ones all have a flange at the compressor outlet. Mine does not. I'm thinking this is not a stock turbo. 

 

 

[Infosecdad]

That's an STi style turbo with that outlet, not an LGT style.

There should be a block on the front of the turbo that's flat with etching as to what it is, but it may or may not be there.

Those look like stock 550 yellow tops, but I don't think they can push 370hp without modifications to them.

I would proceed with caution, make no assumptions, and question everything at this point.

It's going to take a bit to figure out what is going on.

Is the tune opensource or access port?

[05LGT25]

32 minutes ago, Infosecdad said:

That's an STi style turbo with that outlet, not an LGT style.

There should be a block on the front of the turbo that's flat with etching as to what it is, but it may or may not be there.

Those look like stock 550 yellow tops, but I don't think they can push 370hp without modifications to them.

I would proceed with caution, make no assumptions, and question everything at this point.

It's going to take a bit to figure out what is going on.

Is the tune opensource or access port?

It has a COBB cable but no controller. The guy I bought it from said it was like that when he got it. He has owned and modified several Subarus and he said he thinks it had COBB at one point but was re-tuned by opensource. I forget why he said he thought that but I remember him telling me that. He only had it for about six months and had too many projects going on and never did anything to it. He just sold it because he didn't have time. 

The rectangular casting block is there on the turbo but nothing stamped on it.

 

[Infosecdad]

If it's open sourced, then you should get a tactrix cable, pull the tune, and post it.

It would tell us max target psi, what size injectors, and a host of other things.

[Pleides]

As others have said, those look like factory injectors, however it's not uncommon to find Deatschwerks injectors that are modified in the OE injector housing. There is a snowball's chance in hell that you're making that much power on stock injectors (most aren't getting more than 300 WHP on the most optimistic of dynos). More likely, you have these: https://deatschwerks.com/products/02j-00-0740-4

Your turbo is an STI location turbo. This car has very much been messed with as that's an overhaul on these. 

As Infosecdad mentioned, if your car is open source tuned then those with the chops can take a look at the map on the car and see what all is messed with. A Tactrix cable is what you want. Can you take a picture of the cable you mentioned you have that you assume is for an Accessport?

Edited May 8, 2023 by Pleides

[05LGT25]

25 minutes ago, Pleides said:

As others have said, those look like factory injectors, however it's not uncommon to find Deatschwerks injectors that are modified in the OE injector housing. There is a snowball's chance in hell that you're making that much power on stock injectors (most aren't getting more than 300 WHP on the most optimistic of dynos). More likely, you have these: https://deatschwerks.com/products/02j-00-0740-4

Your turbo is an STI location turbo. This car has very much been messed with as that's an overhaul on these. 

As Infosecdad mentioned, if your car is open source tuned then those with the chops can take a look at the map on the car and see what all is messed with. A Tactrix cable is what you want. Can you take a picture of the cable you mentioned you have that you assume is for an Accessport?

As far as the injectors, even if I removed them, would I be able to find a part number on them to know for sure what size they are? I agree with you in regards to the HP. I did about every mod under the sun on my last Subaru including a larger turbo (not a rotated turbo setup) and this car puts me back in the seat way more. I was quite surprised when I test drove it because I expected less. If this car was modded safely and properly and I just have a couple of driveability bugs to work out, then I'm thrilled to have it. 

If I end up taking this into a tuner, would the shop have that Tactrix cord? Or would I buy the tune kit and take it in with me? I'm new to the tune stuff. My last one used EcuTune and the shop did everything for me (this was 15 years ago or so).

Here's the cord that was in the car (draped around the steering column under the dash trim) :

 

[Pleides]

5 minutes ago, 05LGT25 said:

As far as the injectors, even if I removed them, would I be able to find a part number on them to know for sure what size they are? I agree with you in regards to the HP. I did about every mod under the sun on my last Subaru including a larger turbo (not a rotated turbo setup) and this car puts me back in the seat way more. I was quite surprised when I test drove it because I expected less. If this car was modded safely and properly and I just have a couple of driveability bugs to work out, then I'm thrilled to have it. 

If I end up taking this into a tuner, would the shop have that Tactrix cord? Or would I buy the tune kit and take it in with me? I'm new to the tune stuff. My last one used EcuTune and the shop did everything for me (this was 15 years ago or so).

Here's the cord that was in the car (draped around the steering column under the dash trim) :

For the part number? Hard to say. I believe Cobb maps show notes from the tuner in them so maybe the tuner would have noted the injector size - not sure about open source. You either have 740 or 850cc sidefeed injectors - I refuse to believe you're running the bone stock injectors to power levels that high as you'd be at like 150% IDC. 850cc is really pushing it for drivability and flow control for sidefeeds and you may just never have a smooth car. Most people skip the upgraded sidefeeds for a whole topfeed conversion. It's kind of odd that the prior owner went through the hassle of upgrading to an STI fitment turbo and left the fuel system mostly alone.

Nowadays it's much harder to do topfeed conversions with these cars due to the Cobb Green Speed changes because of EPA pressure - so no TGV deletes are allowed (which are basically a requirement to do a proper topfeed conversion on these cars), no emissions check engine lights can be deleted, CARB-friendly catalytic converters only, etc on Cobb tunes after April 2022. Opensource tunes are the way to go nowadays for these cars since they're still old enough that some tuners will open source tune them - ya just have to find one who will do it. If your car was married to an Accessport it may not be easy-peasy to just switch to an open source tune - some others might be able to speak there. I went reverse of that and now my car is stuck with the tune I got back just before the Green Speed changes went through.

If you take a to a tuner... well good luck. Yes, many will have a Tactrix cable and can read the tune info but many will not be able to re-tune the car as many shops are beholden to Cobb and Accessport tuning. My shop here in Portland, Surgeline, exclusively tunes cars on the Accessport and have nearly no tuning clientele now. And yes, that cord is for an Accessport. 

[m sprank]

If you pull the injectors for a clean and flow test you will find out the size.  There is no longer support for side feed, so if the injectors are the issue you dont have much choice. 

Deff not a stock turbo.  As others have stated the new regulations make "fixing" this much more difficult.

[05LGT25]

I appreciate all of your help. This puzzle is starting to make sense. I just need to find the missing pieces. Funny thing is, since I started this thread Thursday, I started the car about 10 times this weekend. Started up normally, no issues, every time. Then just today, two starts were crazy long crank again. So random.

I'm seriously hoping if it's something stupid like a crank sensor, bad ground, etc, I'll find it and can just drive the car the way it is. I love the power. I still definitely want to get it into a tuner to make sure it's done safely or at least install an A/F sensor just to make sure I'm not leaning out. 

[m sprank]

Could be the fuel pressure regulator on its way out.  Have seen it a few times in older WRX.  If you can verify fuel pressure via a manual (temporary) gauge it should be around 39-41psi at idle and rising 1psi with each psi of boost.

[Pleides]

Has a vacuum leak been ruled out?