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2000 RS Coupe
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Are the lines exiting the unibody in the image from the passenger or driver side of the vehicle? I'm assuming driver, side but clarification might get you better suggestions as to what's wrong or how to fix.
 

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'01 2.5RS STM Sedan
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Those are the lines that exit from the cabin on the drivers side and then route up and above the gas tank.

There's three probable causes going on here.
  • First, and what I believe is most likely in your case judging by the outrigger frame and surrounding unibody, is the fuel tank seam that joins the two halves is separating at the halfway mark, due to rust, and causing a leak. The only fix in this case is to drop the tank and replace it (expect over $1000 in labor at a shop as the majority of the rear suspension has to come out--not an easy job and a lot can go wrong here with a rusty vehicle).
  • Second, the gasket on top of the tank for the sub-level sender can be leaking. To verify this, in the trunk/near rear seats there should be two access ports. Unscrew the lids and do a visual inspection to see if there are any leaks coming from the senders.
  • Finally, there could be a bad line. The fuel feed on the later-years (1999? onward) utilize a nylon feed-tube with a quick disconnect. See the image below. This line will not rust, but could potential develop a hole some how. Alternatively, one of the other lines that run atop of the tank could have developed a hole cause a leak. Again, these could be checked via visual inspection through the inspection holes in the trunk area.
I have attached some reference images below.

86475

86474


If you're mechanically inclined, this is a doable job. I have replaced three fuel tanks at this point now, all Northeastern vehicles. However, they all have had their challenges and it can become a time consuming and frustrating task at points. Best of luck.
 

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On my coupe, the gas tank itself was leaking from the seam in one corner. Upgraded to a 2nd gen Impreza tank, bolts right up but required a longer tank strap on one side.
 

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2000 RS Coupe
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Those are the lines that exit from the cabin on the drivers side and then route up and above the gas tank.

There's three probable causes going on here.
  • First, and what I believe is most likely in your case judging by the outrigger frame and surrounding unibody, is the fuel tank seam that joins the two halves is separating at the halfway mark, due to rust, and causing a leak. The only fix in this case is to drop the tank and replace it (expect over $1000 in labor at a shop as the majority of the rear suspension has to come out--not an easy job and a lot can go wrong here with a rusty vehicle).
  • Second, the gasket on top of the tank for the sub-level sender can be leaking. To verify this, in the trunk/near rear seats there should be two access ports. Unscrew the lids and do a visual inspection to see if there are any leaks coming from the senders.
  • Finally, there could be a bad line. The fuel feed on the later-years (1999? onward) utilize a nylon feed-tube with a quick disconnect. See the image below. This line will not rust, but could potential develop a hole some how. Alternatively, one of the other lines that run atop of the tank could have developed a hole cause a leak. Again, these could be checked via visual inspection through the inspection holes in the trunk area.
I have attached some reference images below.

View attachment 86475
View attachment 86474

If you're mechanically inclined, this is a doable job. I have replaced three fuel tanks at this point now, all Northeastern vehicles. However, they all have had their challenges and it can become a time consuming and frustrating task at points. Best of luck.
Hey Silver...any chance you could forward me the lower image of the gas tank so I could enlarge it? I have to address a fuel leak on my daughter's 97 Impreza from a broken line coming from the "rollover valve" to the top of the tank - Suby illustrations show parts and numbers but not a clear image of where the connections are in relation to placement on top of the tank. The image above is perfect and would rally help me out to visualize how to fix this damn thing. Thanks. Sorry Zunfix - not trying to steal your thread.
 

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2000 RS Coupe
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Those are the lines that exit from the cabin on the drivers side and then route up and above the gas tank.

There's three probable causes going on here.
  • First, and what I believe is most likely in your case judging by the outrigger frame and surrounding unibody, is the fuel tank seam that joins the two halves is separating at the halfway mark, due to rust, and causing a leak. The only fix in this case is to drop the tank and replace it (expect over $1000 in labor at a shop as the majority of the rear suspension has to come out--not an easy job and a lot can go wrong here with a rusty vehicle).
  • Second, the gasket on top of the tank for the sub-level sender can be leaking. To verify this, in the trunk/near rear seats there should be two access ports. Unscrew the lids and do a visual inspection to see if there are any leaks coming from the senders.
  • Finally, there could be a bad line. The fuel feed on the later-years (1999? onward) utilize a nylon feed-tube with a quick disconnect. See the image below. This line will not rust, but could potential develop a hole some how. Alternatively, one of the other lines that run atop of the tank could have developed a hole cause a leak. Again, these could be checked via visual inspection through the inspection holes in the trunk area.
I have attached some reference images below.

View attachment 86475
View attachment 86474

If you're mechanically inclined, this is a doable job. I have replaced three fuel tanks at this point now, all Northeastern vehicles. However, they all have had their challenges and it can become a time consuming and frustrating task at points. Best of luck.
What year, make, & model vehicle is the pictured gas tank for?
 

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'01 2.5RS STM Sedan
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What year, make, & model vehicle is the pictured gas tank for?
The one above came out of a 2006 WRX STI.
Here is a picture of my 2001 2.5RS fuel tank when pulled:
86496

Capacity between the AWD tanks is the exact same - 15.9 gallons. The only difference in GC vs GD tanks is the baffling, as well as the cut valves and the center vent valve. However, the components are swappable and I am running 2001 RS everything evaporative equipment in the GD tank with zero codes (fuel pressure sensor, cut valves, vent valve, senders).
86497
86498

RS Baffle on the left, GD baffle on the right. Notice the GD baffle has a top portion as well as is wider--this is due to the fuel pump on the GD's came equipped with an additional surge box situated around the pump pickup.
86499

GC cut valves on the left, GD cut valves on the right. Center is a GD vent valve, but visually the same to the GC one - however, part number is different. I am unaware of the actual difference.

Pictured below is a earlier style AWD tank. Notice the lack of the center vent valve. This tank can be made compatiable on new emissions style setups, please see this post for more information.
86500
 

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'01 2.5RS STM Sedan
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I went through my photos and labeled some lines, equipment, etc. to hopefully aid in anyone who is looking at the daunting mess that is OBD2 evaporative equipment.

First things first, there are a couple of other things I forgot to mention above that I should point out. The 93-95 fuel tanks are a bit different as I believe they were a single saddle design. The early tanks (pre-facelift) are not something I am entirely familiar with, so mileage may vary there.

The GD tanks also have drain ports (big plus in my book). Some have them on one side only, some have them on both. I am not sure why this is, as I have seen some 2005 Forester's with both yet my 2006 tank only has the one. Either way, it makes emptying the tank prior to removal a breeze compared to siphoning with a pump.
86508


The GD tanks also had an additional vapor purge solenoid mounted directly next to the fuel pressure sensor on the top of the tank. I am not sure exactly why the inclusion of this, but it exists. It can be removed for use in a GC with the mounting bracket left open. See below.
86513


Next up I just have some labeled photos of the GC evap equipment on an OBD2 equipped, rear charcoal canister vehicle.

Rollover Valve
86509


86510

86511

86512


Finally, I have an image of the GD tank mounted in my 01' RS. Very tight fit. I believe there are some points of contact to the chassis, as suggested by the rubber insulators mounted on certain faces of the tank. A commenter above suggested different tank straps -- this was not true in my case. After reviewing some part numbers, the GC tank straps cross over until 2005 on various Impreza and Forester models as well. I believe the only change on the newer ones superceding these models is the addition of more studs along the bottom of the straps for additional heat shielding. What is true, however, is that one tank strap is longer than the other. The straps should be marked LH and RH with an arrow indicating direction. To mount the fuel tank, use the short bolts in the front and let the straps hang. Then, the two longer bolts mount in the rear which guide the tank up during tightening.
86514

If I am missing anything, or if there is anything else you would like to see, let me know as I most likely have a picture of it somewhere.
 

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Discussion Starter · #13 ·
I went through my photos and labeled some lines, equipment, etc. to hopefully aid in anyone who is looking at the daunting mess that is OBD2 evaporative equipment.

First things first, there are a couple of other things I forgot to mention above that I should point out. The 93-95 fuel tanks are a bit different as I believe they were a single saddle design. The early tanks (pre-facelift) are not something I am entirely familiar with, so mileage may vary there.

The GD tanks also have drain ports (big plus in my book). Some have them on one side only, some have them on both. I am not sure why this is, as I have seen some 2005 Forester's with both yet my 2006 tank only has the one. Either way, it makes emptying the tank prior to removal a breeze compared to siphoning with a pump.
View attachment 86508

The GD tanks also had an additional vapor purge solenoid mounted directly next to the fuel pressure sensor on the top of the tank. I am not sure exactly why the inclusion of this, but it exists. It can be removed for use in a GC with the mounting bracket left open. See below.
View attachment 86513

Next up I just have some labeled photos of the GC evap equipment on an OBD2 equipped, rear charcoal canister vehicle.

Rollover Valve
View attachment 86509

View attachment 86510
View attachment 86511
View attachment 86512

Finally, I have an image of the GD tank mounted in my 01' RS. Very tight fit. I believe there are some points of contact to the chassis, as suggested by the rubber insulators mounted on certain faces of the tank. A commenter above suggested different tank straps -- this was not true in my case. After reviewing some part numbers, the GC tank straps cross over until 2005 on various Impreza and Forester models as well. I believe the only change on the newer ones superceding these models is the addition of more studs along the bottom of the straps for additional heat shielding. What is true, however, is that one tank strap is longer than the other. The straps should be marked LH and RH with an arrow indicating direction. To mount the fuel tank, use the short bolts in the front and let the straps hang. Then, the two longer bolts mount in the rear which guide the tank up during tightening.
View attachment 86514
If I am missing anything, or if there is anything else you would like to see, let me know as I most likely have a picture of it somewhere.
How much fuel do you drink on a daily basis? Haha thanks man.
 

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2-cars, 10-doors
1998 OBS V7, white/gray/gold
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So much good here. I've got my car on jacks for engine rebuild, engine out, which is relevant to the below. I have a fuel leak in the same spot as OP and I believe due to #3 (quote below).

Finally, there could be a bad line. The fuel feed on the later-years (1999? onward) utilize a nylon feed-tube with a quick disconnect. See the image below. This line will not rust, but could potential develop a hole some how. Alternatively, one of the other lines that run atop of the tank could have developed a hole cause a leak. Again, these could be checked via visual inspection through the inspection holes in the trunk area.
I just drained the tank using the fuel pump (took fuel exiting in engine bay) expecting to slide under the car and confirm where leak is coming from - no leak. Thus i'm thinking a return hose (leaked with engine in, thus fuel returning, no leak with just the feed running fuel). I checked the inspection holes and didn't see anything glaring but this was after engine out and thus return line not used for a bit. I did not plan my order of operations on this project well, admittedly.

Would the fix for these hoses (#3 quote above) also require the tank to be dropped? Would be a good time to upgrade some 25 yo bushings...

Also considering replacing the tank, but I've been all over other (UK / type-ra.com) sites and see a lot of fellas refurbishing these tanks and keeping their stock/OEMness since they got the "good" ones (for resale, collector, etc.).

Any recommendations on better STi vs. WRX or n/a for a tank from 2002-2007? I've seen commentary more/better baffling in STi tanks (Another good reference) and best to use that. Trying to eradicate any track fuel starvation issues and I will be redirecting the return lines to the internal tank baffle. As a wagon owner it's not as easy to create a new fire wall for any surge tank in the trunk/hatch. I'll need to figure out who to source a tank from as well as they're ~500 from Subaru..
 

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'01 2.5RS STM Sedan
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Would the fix for these hoses (#3 quote above) also require the tank to be dropped? Would be a good time to upgrade some 25 yo bushings...
Yes, the tank has to be dropped.

Also considering replacing the tank, but I've been all over other (UK / type-ra.com) sites and see a lot of fellas refurbishing these tanks and keeping their stock/OEMness since they got the "good" ones (for resale, collector, etc.).
If you have to drop the tank, I recommend replacing it with a new unit as well as all new vent/check valves while you're in there. It can be easily an 8hr job just getting it out, depending on how many bolts you have to fight with along the way.

Any recommendations on better STi vs. WRX or n/a for a tank from 2002-2007? I've seen commentary more/better baffling in STi tanks (Another good reference) and best to use that. Trying to eradicate any track fuel starvation issues and I will be redirecting the return lines to the internal tank baffle. As a wagon owner it's not as easy to create a new fire wall for any surge tank in the trunk/hatch. I'll need to figure out who to source a tank from as well as they're ~500 from Subaru..
WRX and STI tanks are identical, they even share the same part numbers. Additionally, a Forester XT tank is identical. Any of them will work just fine. I highly recommend sourcing a used or new OEM tank. The aftermarket ones are not great, having used them in the past. I purchased a used STI tank on eBay a couple years ago now for roughly $275 shipped.
 

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Both OP and ballz_anthony should have looked at their fuel pump through the access hole under the rear seat. either the lines at the pump, or the pump gasket can leak too. As you can see in OP picture, though fuel under pressure can spray, it appears to me that OPs leak is coming from the top of the tank. The hoses are moist, but not near where they are clamped.

One wild thing with leaks, and it's the difference between a good and bad diagnostician, is being able to determine where it's coming from. Leaks end up getting every where especially if the car is driven, because... 35-90mph winds blow some shit around.
 

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2-cars, 10-doors
1998 OBS V7, white/gray/gold
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@Silverbullet_RS or anyone - found a few people with tanks. Curious how one has received a fuel tank shipped? Estes or some LTL freight (less than truckload / freight service) or USPS/UPS/FedEx? A gentleman said he'd ship one from the west coast if I was able to arrange for shipment... is it still hazardous if it hasn't had fuel in it over a year?... or has been thoroughly washed/cleaned?

Worst case I have an eBay option but they're terrible with questions. I'd basically have to see how it arrives and likely drop another $200+ in missing pieces. Surely they took a picture of it and threw it up on the rack to sell months later - difficult to answer questions with it out of sight..
 

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'01 2.5RS STM Sedan
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@Silverbullet_RS or anyone - found a few people with tanks. Curious how one has received a fuel tank shipped? Estes or some LTL freight (less than truckload / freight service) or USPS/UPS/FedEx? A gentleman said he'd ship one from the west coast if I was able to arrange for shipment... is it still hazardous if it hasn't had fuel in it over a year?... or has been thoroughly washed/cleaned?

Worst case I have an eBay option but they're terrible with questions. I'd basically have to see how it arrives and likely drop another $200+ in missing pieces. Surely they took a picture of it and threw it up on the rack to sell months later - difficult to answer questions with it out of sight..
Tank should not required to be shipped via freight. It fits within weight and dimension limits (for UPS and FedEx, not USPS). I had a couple shipped to me via Ground before no problem. Should not need to be labeled as hazardous as long as its drained and fully evaporated after a period of time, but I am not in the shipping industry to make a judgement. The ones shipped to me had no such labeling however.
Sleeve Automotive design Personal protective equipment Sportswear Denim
 

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Rollover Valve
View attachment 86509





Question what is this valve exactly is it necessary? Where can I get one ?. I did a fuel tank swap from a forester from before 2001 can't remember the exact year, it had this valve on one of the lines and it broke. Would it be a problem if I mount the tank into my97 ra sti without this valve ?[/QUOTE]
 

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Rollover Valve
View attachment 86509





Question what is this valve exactly is it necessary? Where can I get one ?. I did a fuel tank swap from a forester from before 2001 can't remember the exact year, it had this valve on one of the lines and it broke. Would it be a problem if I mount the tank into my97 ra sti without this valve ?
The Rollover valve prevents fuel from leaking out of the fuel tank and the lines attached to it in the event of a rollover accident. Personally, I would leave it installed.

Where can you get one? I am not sure, atleast new. The one picture (42084KC060) is discontinued. Maybe the older style (42084AA120) fits? They look very similar. I would try and find one used locally to you or online. They came on every Subaru of the era.
 
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