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Discussion Starter #1 (Edited)
Disclaimer:

There is some oversimplification here, but the intent is to help out when planning a swap or for self-diagnosis of issues. The info below is provided as resource in the hope that it helps the forum. If you break something because you used this info, that’s unfortunate. I put this together myself and while it worked for me, it may not work for you. That said, if you find a mistake, send me a PM or an email and I’ll take a look. If you have any questions, post them and I’ll add them to the Q&A section.

Overview:

All of the EVAP fuel vapor purge systems are designed to do the same thing: manage fuel vapors while the fuel tank expands and contracts, and manage the high volume of vapors created during fuel fill up. While technically an emissions system, it's not like a smog pump from back in the day. There is no performance hit from having a working EVAP system in place. However, there can be some performance problems when it is not working as the ECU expects the change in AFR when purging. With a non-working EVAP system there is also the likelihood that you will get fuel smell in the cabin, especially after fill up. Or that your garage will reek of fuel when you park inside. Or that you will have a really hard time putting in fuel... Maybe this sounds familiar: fill for 5 seconds and the pump shuts off. Repeat for 15 minutes to fill the tank. Dump fuel on the side of the car in the process.

Let’s fix all that.

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Older USDM and JDM systems (Background)

From all I have seen, the purge valve works the same on all of the engines (NA, turbo, USDM, JDM, etc). When certain conditions are met (ex.- not under heavy acceleration or boost), the valve is opened to draw vapor laden air into the intake and fuel trim is adjusted to compensate. This purges the canister of vapor so that the activated carbon inside can be ready for the next fuel tank expansion or fuel fill. If the purge is not working correctly, the canister will become saturated and ultimately unrecoverable (it actually gets heavier with fuel).

The purge valve is located on the intake manifold, and is actuated by the ECU.



These systems are “open” in that while some of the fuel vapor is collected in the charcoal canister, some escapes out of the vented fuel filler cap. The fuel filler neck also has a large side pipe that helps the tank vent fumes up to the fill nozzle during fuel fill up.



Older USDM Suby’s and all of the popular older JDM swaps have an engine bay mounted charcoal canister. It is round and mounts behind the right front headlight (when viewed from the driver’s seat). Most are 2-port, some are 3-port, and a few are 4-port.

The most common is the 2-port. It was used in a number of non-turbo USDM applications (ex. ‘91-94 EJ22, ‘97 outback wagon, etc). It was also used in early EJ20G’s, EJ20K's, and version 5/6 EJ207’s. If you need to replace one, you can use part number 42036AA000 (from a 1996 Legacy Sedan 2.5GT with manual trans, matches 2-way valve listed below).



Port usage on this style canister:

  • One (smaller) hose from the canister to the purge valve.
  • One (larger) hose from the canister to the vapor line that runs to the fuel tank.

The next most common is the 3-port. Some EJ20G’s and some USDM chassis (early ‘90s turbo legacy) came with a 3-port canister.



Port usage on this style canister:

  • Same as 2-port.
  • Same as 2-port.
  • The third line is an auxiliary purge line to draw in vapors when the car is under boost.

Really early cars and perhaps a few other oddballs had a 4-port charcoal canister (think ‘88 GL). You don’t want one of these.



Port usage on this style canister:
1-4.) Don’t care, you’ll need a different DIY for that one.

Some of the canisters have a mechanical 2-way valve mounted on the larger hose between the intake manifold (technically the fuel tank) and the canister. This valve helps maintain the pressure equilibrium in the fuel tank and charcoal canister without ECU control. If you need one, it can be sourced from a 1996 Legacy Sedan 2.5GT with manual trans, part number 42084PA050 (matches 2-port canister listed above).



On turbo cars, there is also a check valve installed in the smaller hose between the intake (technically the purge valve) and canister. This prevents the canister and fuel tank from being pressurized under boost. If you need one, I haven't found a good USDM replacement. You might try part number 86634AA010, which is a washer nozzle check valve. However, a check valve designed for vapor might work better in the long run versus something designed for fluid. If someone comes up with an alternative, post below and I'll look into it. For reference, the following system has both a mechanical 2-way valve and the correct check valve (canister has been removed):



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Newer USDM systems (Background)

Newer USDM Suby’s have an ORVR system (onboard refueling vapor recovery) which includes a much larger rear mounted charcoal canister box.



The systems are “closed” in that the filler cap is sealed and all venting occurs through the charcoal canister. Only a very small amount is routed up the filler neck and it is used to trigger the fuel nozzle shut off to prevent overfilling.



There is also an ECU/electrically operated vent valve (sometimes called the Drain Valve), an ECU/electrically operated 2-way valve (sometimes called the Pressure Control Solenoid Valve), a fuel tank pressure sensor, and a fuel tank temperature sensor. The vent and 2-way valves are located above the charcoal canister box in the rear of the vehicle while the pressure and temperature sensors are mounted in the fuel tank.

The vent valve is installed between the canister and outside air. It is “normally open”, in that it remains open even when all system power is removed. The ECU closes the vent valve to test the system for leaks and to test operation of the fuel tank pressure sensor.



The 2-way valve is installed between the charcoal canister and the fuel tank, with a reference to outside air pressure. It is directional (there is an arrow embossed on it) and the state of the valve is determined by the ECU. Basically, it is used to actively regulate the pressure of the fuel tank, both during system testing and normal use.



This is what the entire charcoal canister/vent valve/2-way valve assembly looks like (left in the picture is toward the rear of the car):



Besides controlling the function of these 3 valves (purge, vent/drain, 2-way/pressure control) and reading the sensors (tank pressure, tank temperature), the ECU also checks to make sure that all of them are in place and function correctly. This is why you get an error code if you remove one of the valves or if any component is vented, loose, leaking, or missing (like your gas cap).

True, you can defeat the error(s) that the newer ECU’s will give if you don't have all the components installed and working, but it will not fix the real problems you will have with gas smell in your cabin, not being able to fill up with gas at the pump, problems with vapor lock (trouble with hot restarts), etc. To me, those are everyday annoying issues that are not worth hacking or having a broken system.

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How to get your swap working

There are basically 4 straightforward ways to do a swap with a correctly working evap system:

1.) Match all the parts.

  • Engine/purge valve.
  • ECU.
  • Charcoal canister.
  • Fuel tank.
  • Fuel filler pipe.
  • Gas cap.
  • 2-way valve.
  • Vent valve.
  • Lines and connections.

This may not be practical for everyone but it will ensure that everything plays nice together, especially if you prefer wrenching over research/diagnostics. If you are using a newer USDM drivetrain into an older body car, this is a good way to pass emissions. If you are using a JDM drivetrain, you aren’t going to pass emissions this way, but the evap system will work and living with the car will be lovely.

I would definitely recommend this route for Pre-OBD2 USDM chassis with a newer USDM turbo engine/drivetrain.

Either way, get everything from the donor car.

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2.) Pre-OBD2 USDM chassis with older/JDM engine.

There is a reason an EJ20G/K swap into a pre-OBD2 car (‘95 L, etc) is so popular - it is about as plug and play as you can get.

Keep installed on the USDM chassis/refresh if necessary:

  • Fuel tank.
  • Fuel filler pipe.
  • Gas cap.
  • Lines and connections.
  • *Round charcoal canister (may not have 2-way valve).

Swap in the following JDM parts:

  • Engine/purge valve.
  • ECU.
  • *Round charcoal canister (may or may not have a 2-way valve, should have a check valve).

*You can use a 2-port or a 3-point canister, but the 2-port is easier to plumb and reduces the number of hoses under the hood. If you want the most simple, working EVAP system with a pre-OBD2 chassis and a JDM turbo swap, use the 2-port.



Even if the charcoal canister is the same between your JDM turbo engine and pre-OBD2 USDM chassis (2-port or 3-port), you need a check valve installed correctly. You can get it from the turbo engine or a generic one in the PCV/random emissions hose barbs at your local auto parts store. Easiest if it came with your swap motor.

If your chassis did not have a 2-way valve installed on the larger line, don’t add one with the JDM engine. Just add the check valve. Here’s the correct orientations for the 2-way valve and the check valve (from a factory turbo version 6 EJ207):



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3.) OBD2 USDM chassis (~’98-01 with rear chassis-mounted charcoal canister) with ~’02 WRX USDM turbo engine.

Also a great/easy swap.

Keep installed on the USDM chassis/refresh if necessary:

  • Charcoal canister.
  • Fuel tank.
  • Fuel filler pipe.
  • Gas cap.
  • 2-way valve.
  • Vent valve.
  • Lines and connections.

Swap in the following ~’02 WRX parts:

  • Engine/purge valve.
  • ECU.

This is basically the same as matching everything as the OBD2 chassis has the correct parts for this swap. Later USDM WRX and STI stuff can be more complicated. Do your homework, but this is pretty well documented and can be emission tested if done correctly.

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4.) OBD2 USDM chassis (~’98-01 with rear chassis-mounted charcoal canister) with JDM turbo engine (originally equipped with round engine bay charcoal canister).

I have personally performed this swap and all is working correctly, so I’ll go into more detail.

Keep installed on the USDM chassis/refresh if necessary:

  • Charcoal canister.
  • Fuel tank.
  • Fuel filler pipe.
  • Gas cap.
  • Vent valve.
  • Lines and connections.

Swap in the following JDM turbo parts:

  • Engine/purge valve.
  • ECU.

Modify/do the following:

  • Remove and save/set aside JDM mechanical 2-way valve from JDM round canister plumbing.
  • Remove and discard short rubber hose from larger metal pipe where JDM 2-way valve was connected to the engine.
  • Disconnect check valve from JDM round canister right at the canister (leaving a little bit of hose hanging from the check valve). Leave connected to smaller metal pipe on engine.
  • Remove JDM round charcoal canister. Sell/archive/discard.
  • Connect loose end of check valve to metal pipe where JDM 2-way valve was connected. Since you will be forcing the smaller diameter hose over too large of a nipple, you might need to use some simple green or spit for lube. (this basically makes a loop between the two metal pipes with a check valve in between)
  • You are done under the hood.
  • Go to the back of the car, you might want to jack up the rear to give more accessibility. Follow normal jackstand safety. I like jacking up the car and sitting it on plastic rhino ramps (which rest under the tires). Way more stable than a jackstand and gives more room under the car.
  • Anyway, remove the 3 nuts holding up the USDM charcoal canister. You can detach the 3 rubber hoses from the canister if you want, or you can let it hang there if you can work around it.
  • Remove the one bolt that holds the rear sway bar bracket and lower the USDM electrical 2-way valve (aka the Pressure Control Solenoid Valve). Take note of the hose routing because it is important. The valve also has an arrow embossed on it. The arrow points towards the rear of the car.
  • Remove the USDM 2-way valve (3 hoses, 1 electrical connection).
    • The electrical connection will not be used anymore. I sealed mine in a nitrile glove and zip tied it out of the way.
    • The small hose is also not used anymore. This hose is a reference to atmospheric pressure, so leaving it open on this end is ok because it is open on the other end, too (opens into vehicle body).
  • In place of the USDM electrical 2-way valve, install the JDM mechanical 2-way valve.
    • I installed mine with the arrow pointing toward the front of the car, opposite of how the USDM valve was installed. Works for me. It may also work with the arrow facing rearward. Feel free to experiment. You will know it is working if you can fill up with fuel without issues.
    • I wrapped the JDM 2-way valve in rubber hose and zip-tied it to the metal bracket that originally held the USDM 2-way valve.
  • Bolt the valve and sway bar bracket back into place.
  • Bolt the canister back into place.
How this works:

  • Bypassing the round canister with the check valve line reconnects the purge valve with the fuel tank vapor line while still protecting the fuel tank from being pressurized.
  • The JDM ECU cannot actuate the USDM electric 2-way valve. Replacing it with the JDM mechanical valve allows the rest of the system to function correctly during regular operation as well as fuel fill up.
  • The USDM drain valve is “normally open” so even though it is no longer ECU-controlled, it will allow the charcoal canister to vent properly in both directions.

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Things I don’t recommend:
1.) Drilling or cutting out the valves in the fuel tank. So when you overfill your tank, you fill up your charcoal canister with raw fuel, awesome. Or when you roll over, all your fuel comes out. Neat.

2.) Removing the charcoal canister altogether. You need the weight savings on your street car? Please. The big box canister is only ~3 pounds new (pushing 5 pounds when vapor saturated and needing replacement). It makes the engine look cleaner? Really, have you seen all of the wires and lines on an EJ?

3.) Putting a mini filter on one of the big vapor lines near the fuel tank. You like the smell of fuel all the time, huh?

4.) Running a mix up of JDM engines and USDM vapor parts other than listed above. You didn’t have that beard when you starting filling up your car at the pump, did you?

5.) Running a mix up of USDM turbo engines and older USDM vapor parts other than listed above. Same beard, worse AFR, now with moar CEL.


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Big thanks to Rob and SIMER for some feedback that helped me sort this out.
 

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This is all really great info but I'm still not sure how to identify problems with my oem bone stock setup. I have the big box in back and I swapped out all 3 valves (the 2 on the box and the one on the filler neck) but it still clicks off when I fill up and I know then tank is not even close to full.

I kinda understand that if the pressure is not able to vent anywhere else it will come out the filler tube but the system is so unfamiliar to me that I don't even know where to start or how to properly diagnose the problem area. PLS HALP
 

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Discussion Starter #4 (Edited)
This is all really great info but I'm still not sure how to identify problems with my oem bone stock setup. I have the big box in back and I swapped out all 3 valves (the 2 on the box and the one on the filler neck) but it still clicks off when I fill up and I know then tank is not even close to full.

I kinda understand that if the pressure is not able to vent anywhere else it will come out the filler tube but the system is so unfamiliar to me that I don't even know where to start or how to properly diagnose the problem area. PLS HALP
There are 2 big hoses that connect to the charcoal box in your system. If I remember correctly, one of them has a hose clamp and one does not. Anyway, while you are at home/have access, loosen and remove one of the large hoses at their connection to the charcoal canister. Then lube the hose end with a little soapy water and reinstall in the correct location (but don't reclamp). Repeat for the other large hose. The point is to make them easy to remove by hand later. Don't mess with the small hose (EVAP), it runs to the purge valve on the engine and has nothing to do with fill up.

Drive to your favorite pump. Try filling up. If the nozzle shuts off, pull off one of the hoses. You should be able to bend down and see them without crawling under the car. Try filling again. If it shuts off again, reinstall that hose and try after removing the other.

If one of these combinations works, you can leave it disconnected temporarily to allow a normal fill up. Go home and look under the car to see which hose is disconnected (it is written on the charcoal can).

If it is the hose than runs to the drain, most of your system is good, you just have a plugged drain. Clean out everything downstream of the charcoal can until you find the problem. Often it is a bug or dirt in the vent that goes into the frame rail. If you cannot easily blow through the drain valve assembly when the car is off (by blowing from where it was connected to the charcoal canister), you have a clogging problem.

If it is the hose than runs to the tank, your charcoal canister is probably shot and needs to be replaced. Take it off completely and weigh it. If it is close to or over 5 pounds, it is saturated and needs to be replaced. New should only weigh a little over 3 pounds, maybe 3.5. A new one costs around $75 shipped, I think.

If disconnecting neither large hose works, the problem is probably in your tank, sorry. The valves and hoses around the fill neck don't do a lot for you for fill-up, they are for shut-off when full and reference for pressure control valve. The fuel pump you are using might also flow too fast for your setup. If you know of a pump that fills a little slower, you might try that, too.

Let me know what you find.
 

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They call me Garrett
98 RBP V4 STi Swapped RS
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This is a great post for info. Also, can confirm EJ20ks have the 2 nipple in engine bay style canister.

Things get dicey when you start swapping gas tanks (GC->GD) but my rule of thumb is to always maintain the evap system made for the ECU and engine you are running.
 

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Fantastic write-up. Thanks for taking the time to clearly document this. When I figured out my solution (#4 on your list), I had to dig through the various sube manuals to get it right. It would be nice to have some part numbers or alternate sources for the 2-way and check valves. I can imagine those not being included with every import motor.

I will also mention that the EDM turbo cars (at least the ej20G variants) do indeed have evap ECU control. Although I am not sure exactly what components that includes.

-Rob
 

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Discussion Starter #7
This is a great post for info. Also, can confirm EJ20ks have the 2 nipple in engine

bay style canister.

Things get dicey when you start swapping gas tanks (GC->GD) but my rule of thumb is to always maintain the

evap system made for the ECU and engine you are running.
Thanks, I'll update about the EJ20K.

I agree, if you have to get into swapping the fuel tanks, stick with Option #1 (swap everything). In that scenario, the only parts from the recipient chassis I would plan to keep would be the hard fuel feed, return and vapor lines that run from the tank area to underhood.

Fantastic write-up. Thanks for taking the time to clearly document this. When I figured out

my solution (#4 on your list), I had to dig through the various sube manuals to get it right. It would be nice

to have some part numbers or alternate sources for the 2-way and check valves. I can imagine those not being

included with every import motor.

I will also mention that the EDM turbo cars (at least the ej20G variants) do indeed have evap ECU control.

Although I am not sure exactly what components that includes.

-Rob
Thanks! Hope it helps someone.

Alternate sources:

  • mechanical 2-way valve - 42084PA050 (sourced from a 1996 Legacy Sedan 2.5GT, manual trans).
  • 2-port charcoal canister - 42036AA000 (matches this 2-way valve).
  • check valve - 86634AA010 might work (washer nozzle check valve). But a check valve designed for vapor might work better in the long run versus something designed for fluid. If someone comes up with an alternative, post below and I'll look into it.

I'll update the write-up above as well.

I haven't put my hands on an EDM turbo setup but it is entirely possible that the EVAP system is different or a combination of what I listed above. If someone replies with their unmolested and confirmed setup, I'll try to work it in.

Generally speaking, if the OEM system has fuel injection, an ECU, and an O2 sensor, it probably at least has an ECU-controlled EVAP purge valve.
 

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There are 2 big hoses that connect to the charcoal box in your system. If I remember correctly, one of them has a hose clamp and one does not. Anyway, while you are at home/have access, loosen and remove one of the large hoses at their connection to the charcoal canister. Then lube the hose end with a little soapy water and reinstall in the correct location (but don't reclamp). Repeat for the other large hose. The point is to make them easy to remove by hand later. Don't mess with the small hose (EVAP), it runs to the purge valve on the engine and has nothing to do with fill up.

Drive to your favorite pump. Try filling up. If the nozzle shuts off, pull off one of the hoses. You should be able to bend down and see them without crawling under the car. Try filling again. If it shuts off again, reinstall that hose and try after removing the other.

If one of these combinations works, you can leave it disconnected temporarily to allow a normal fill up. Go home and look under the car to see which hose is disconnected (it is written on the charcoal can).

If it is the hose than runs to the drain, most of your system is good, you just have a plugged drain. Clean out everything downstream of the charcoal can until you find the problem. Often it is a bug or dirt in the vent that goes into the frame rail. If you cannot easily blow through the drain valve assembly when the car is off (by blowing from where it was connected to the charcoal canister), you have a clogging problem.

If it is the hose than runs to the tank, your charcoal canister is probably shot and needs to be replaced. Take it off completely and weigh it. If it is close to or over 5 pounds, it is saturated and needs to be replaced. New should only weigh a little over 3 pounds, maybe 3.5. A new one costs around $75 shipped, I think.

If disconnecting neither large hose works, the problem is probably in your tank, sorry. The valves and hoses around the fill neck don't do a lot for you for fill-up, they are for shut-off when full and reference for pressure control valve. The fuel pump you are using might also flow too fast for your setup. If you know of a pump that fills a little slower, you might try that, too.

Let me know what you find.
So I finally drove enough to need gas and when I filled up I disconnected the hose with the clamp first. I was able to fill 10.9 gallons without it clicking off and I thought the tank was full since it wasn't totally on E yet but after starting it up the needle is about a gallon shy of full tank. I'm going to remove the other hose next time I fill up and see if there is an improvement with that one also. Haven't yet measured the can to see if it is saturated but if disconnecting either hose makes a big difference does that mean it is the can or do both sides of the system probably have a clog? Sorry for supernoob spoonfeeding session but yeah...
 

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This time I disconnected the hose without the clamp and it stopped after 6 gallons. Put that one back on and disconnected the one with the clamp and it filled all the way to full with no issues. Pretty sure I have isolated the problem to the hose with the clamp, it is the one in the middle labeled 41 in the schematic

 

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I'm swapping an 06wrx engine and gas tank into my 98rs, can I use my 98rs charcoal canister (rear mounted)? The 06 wrx gas tank didn't come with the matching charcoal canister.

Thanks!!!
 

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Discussion Starter #11
This time I disconnected the hose without the clamp and it stopped after 6 gallons. Put that one back on and disconnected the one with the clamp and it filled all the way to full with no issues. Pretty sure I have isolated the problem to the hose with the clamp, it is the one in the middle labeled 41 in the schematic
Sounds like it is either a clogged drain or a saturated charcoal canister. You should be able to read the words printed on the canister to tell you which (says "DRAIN" above one of the ports). Follow the notes in my previous post on what to do next.

I'm swapping an 06wrx engine and gas tank into my 98rs, can I use my 98rs charcoal canister (rear mounted)? The 06 wrx gas tank didn't come with the matching charcoal canister.

Thanks!!!
Unfortunately, I am not very familiar with the newer systems but the charcoal canister looks similar. If it has 3 ports (big unmarked, big "DRAIN", and small "PURGE"), I say go for it and report back.
 

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Free Supers!!!
08 Fozzy, 94 Toyota Hilux
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What about swapping a newer usdm wrx engine in a older Legacy that has the engine bay mounted charcoal canister.
 

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Discussion Starter #13
What about swapping a newer usdm wrx engine in a older Legacy that has the engine bay mounted charcoal canister.
As I mentioned, I am not as familiar with the newer USDM systems. Regardless, it depends on how new, what ECU you are running, and what sensors/solenoids that ECU is looking for. On a 2000 USDM 2.5RS, which I am familiar with and know has at least some of the same components of a newer WRX, you will have fuel temp sensor, fuel tank pressure sensor, and a fuel tank pressure control valve - none of which will be in the older Legacy fuel tank. Generally speaking - match fuel tank/pump/lines, charcoal canister, fuel fill pipe, ECU, and engine. If you don't want to do that, and there isn't good documentation, you are kind of on your own to figure out how to splice the systems together. Sorry I couldn't be more helpful.
 

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Thanks for the info! Not sure if im gonna end up with two but my 96 brighton didnt have an evap can at the front passenger side and my jdm ej25d is definitely missing one there. Gonna slap a two hose in there soon
 

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Free Supers!!!
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Thanks guys. Hopefully I wont have any codes, but worse comes to worse I'll have them programmed out of the WRX computer. The Legacy is a 97 with the front mount canister and my swap is a I believe 03-04 WRX. I might do a write up on it to help people out.
 

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This is a great thread! I've run into a bit of a problem though, I am using option #4, a 1994 wrx sti ej20g engine into a 99 rs body, however I can't seem to locate my purge solenoid, it looks like it was removed by the previous owner. I am trying to reinstall a replacement solenoid but I'm unsure of the hose routing, does anyone know if I can route it in the loop where the original jdm mounted front charcoal canister was? Thanks for the help!

Edit: See post below, solution found on opposed forces
 

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Discussion Starter #18
This is a great thread! I've run into a bit of a problem though, I am using option #4, a 1994 wrx sti ej20g engine into a 99 rs body, however I can't seem to locate my purge solenoid, it looks like it was removed by the previous owner. I am trying to reinstall a replacement solenoid but I'm unsure of the hose routing, does anyone know if I can route it in the loop where the original jdm mounted front charcoal canister was? Thanks for the help!
The evap purge solenoid should be mounted on/under the intake manifold. It looks pretty similar, if not identical, to the one from your 99rs motor (if you still have it to compare).

But your ej20g might not have one. If you have an unaltered engine wiring harness and there isn't an extra plug, then you either have an evap solenoid and haven't located it yet or your motor doesn't have one. I would not add one if your ECU isn't looking for it. Do you have a pinout for your ECU?

I'm more familiar with the V5/6 parts than the older JDM motors. Someone else might be able to help you out if my thoughts don't lead you onto the right track.
 

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Thanks for the reply! I have been pouring over the fsm and the wiring diagrams and there is definitely a plug for the evap purge solenoid and like you mentioned it is under the passenger side of the intake manifold. The actual solenoid isn't there however so that's why I'm confused about the hose routing. I wish I could take a look at the original rs motor but I installed the g in the car a few years ago and it replaced a motor which was also not the original motor that the owner before me put in. This summer I replaced the entire evap system and the fuel tank due to a copious quantity of rust, and the fact that it took forever to fill up! This appears to be the last piece of the puzzle before I have a completely working system.

Edit: Looks like I've found my solution via opposed forces, there is a nice diagram on there of the ej20g solenoid setup...here is the link if anyone needs the info...thanks again!

http://opposedforces.com/parts/impr...system_turbocharger/fuel_pipe/illustration_1/
 

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Discussion Starter #20
Thanks for the reply! I have been pouring over the fsm and the wiring diagrams and there is definitely a plug for the evap purge solenoid and like you mentioned it is under the passenger side of the intake manifold. The actual solenoid isn't there however so that's why I'm confused about the hose routing. I wish I could take a look at the original rs motor but I installed the g in the car a few years ago and it replaced a motor which was also not the original motor that the owner before me put in. This summer I replaced the entire evap system and the fuel tank due to a copious quantity of rust, and the fact that it took forever to fill up! This appears to be the last piece of the puzzle before I have a completely working system.
Are the two open lines for the purge solenoid still under there somewhere, maybe capped?
 
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