818 fuel components needed ?

[Larry J W]

I have decided to go with a JDM front clip as a partial donor. Going over the wiring diagram to source the additional parts required, I have a couple of questions. Beyond what is supplied with the kit and a fuel pump which of the following do I need? The USDM pin outs on the ECU are shown after the component. Yes I realize the JDM ECU pin outs are different.

Fuel control unit (A13, D15)
2 Tank level sensors (B25)
Fuel temp sensor (B6)
Pressure solenoid (E22)
Drain valve (E11)
Control Valve (E23)
Pressure sensor (B15)

Also is there an inertial cut off switch to kill the fuel system in case of a crash? Don’t you just love computers and wiring!
Larry

[Larry J W]

With help from fateo66 and lots of time in the service manual I may have the answers to the 818 fuel system requirements. The fuel control unit, temperature sensor, and level sensor are required to run the engine on a Subaru ECU. The fuel control unit is located in the right rear quarter. The level and temperature sensors are located with the fuel pump assembly.

The other four devices are used with the charcoal canister. I am pretty sure that the ECU will energize a check engine light if they are not connected. If you live in a state that has emission checks, these parts will be needed. In Colorado we are lucky in that kit cars are exempt from emission requirements. This is because of the hard work from the Colorado Collector Car Console working with the state legislature. If there is a chance the 818 will be sold to someone in a state that has emission inspections it would be good include them in your build.
If any of this is in error please correct!

Larry

[metalmaker12]

That can all be tuned out and will pass emission with a factory ecu

[Mechie3]

The manual calls for the pump itself and a connector as the only parts from the in tank assembly. They give you a new in tank mounting bracket and level sensor.

[Larry J W]

Looks like the fuel pump controller is required. See the pictures on pages 228 and 234 of the manual. Prices on ebay are in the $50 dollar range.

[dougkirkbride]

21002

I have been working on my donar vehicle getting the necessary fuel parts removed:
after researching the dissasembly, build manual, owners manual and what you all have stated above here is what I determine as needed parts:

all of the items below seem to be attainable without dropping the tank:
need the fuel pump assembly from oval hole in tank- mark connector on wiring harness as this will be spliced to new FFR connector
need the OEM subaru Fuel filter - havent found this yet - must be in engine compartment - OEM owners manual states this is part of the fuel pump.
need the fuel pump control unit - this is above the canister in the back quarter panel- as larry states above pages 228 & 234 of assy manual - assuming the wires from the pump and level/float come to this before going to the ECU ??
need the vapor canister - lots of questions here , the assy manual states to attach hose from breather to this unit then attach the oem/subaru supplied lines coming out of the canister to the engine at there original lengths. the picture in the dissassembly manual (page 41) shows two units/devices, neither looks like they have a wiring connector going to them. the unit in the back of my car has a wiring connector going in the end.

My donar is a 2006 WRX wagon, dont want to drop tank if i dont have to, have a buyer for the chasis.

Questions:


Vapor canister, Charcoal filter all the same device correct?


Where is the fuel filter? other than the one built into the pump/tank and the "sock"?

Does all the info above make sense? is anything else needed for the fuel delivery system?

Is the fuel sub level sensor plug needed or the fuel level sensor plug needed for the 818? the OEM manual shows the fuel level sensor as part of the fuel pump?

I tried to better understand it by creating a simple schematic....please see schematic.....am I out in left field?

How many lines/hoses from the vapor canister to the engine are needed?

Emissions...Emissions oh lets simplify the Emissions, simplification is what i am looking for but I still want everything to work without the idiot lights when i fire it up.

Thanks,
Doug

[JAubin]

Bumping this because I'm finally looking at my fuel system on the donor. I'm planning on getting an aftermarket fuel pump anyway, so in that case would I be able to grab the harness, and fuel pump controller and not reuse any of the other components from the wrx in-tank fuel system? Would also be nice to not drop the tank and just leave it all intact.

[Mechie3]

You can pull all the in tank stuff from the trunk behind the passenger side seat. No need to drop the tank.

[JAubin]

Yeah I just dug into that and it's a disgusting corroded mess under the access panel...just thinking out loud if I could skip even opening up the tank. Not that it would be a big deal to pull the cap, gut it, and replace I guess.

[wallace18]

You need the fuel filter and bracket. Though you can also make a aftermarket one work.

[dougkirkbride]

I couldnt get the harness without dropping the tank. i didnt need to drop the tank all the way, just drop back side of straps and lower the tank towards the back of the car enough to get to the wire connector in the middle of the tank. all simple to do once you remove the whole rear differential and axles :) Pulling the gas inlet hose off from the fill tube takes some muscle but will come off.

[longislandwrx]

Newer cars didn't have the fuel filter, just a sock on the pump. I think only 02/03 came with an engine compartment filter.



I wouldn't go crazy with evap system and the charcoal can, Pretty sure the first version of the manual just said run a length of tube into the rocker panel for a vent. All the codes for evap can be defeated,

but to answer your question, it's one hard line that goes from the purge solenoid on the intake manifold to the charcoal can and a electrical connector comes from the ecu.

and your diagram looks spot on.

[RM1SepEx]

My 05 only had the fuel filter in the tank, no external filter

[Triathletedave]

Can someone please post a picture of the fuel temp sensor. I can't seem to identify this unit. My donor is a 2005 RS Wagon.

Thanks

[Bob_n_Cincy]

Can someone please post a picture of the fuel temp sensor. I can't seem to identify this unit. My donor is a 2005 RS Wagon.

Thanks

It's right above the pre-pump filter with 2 little wires attached to it.
3/8" diameter about 1" long
33897

[Triathletedave]

It's right above the pre-pump filter with 2 little wires attached to it.
3/8" diameter about 1" long
33897

Found it. Thanks Bob. Since there are no instructions on where to install it, what have others done? Simply splice it into the ecu line and ground it! I assume it just provides the appropriate resistance to enable the temp control and activate the fuel pump?

Dave

[Bob_n_Cincy]

Found it. Thanks Bob. Since there are no instructions on where to install it, what have others done? Simply splice it into the ecu line and ground it! I assume it just provides the appropriate resistance to enable the temp control and activate the fuel pump?

Dave
I don't know how it is used by the ECU. I do know it throws a code if you don't hook it up.
Aloha put a resistor in place. See thread:
http://thefactoryfiveforum.com/showthread.php?11586-Honolulu-818S-Hana-(work-build)-Thread&p=167924#post167924

post 799 to 801 and 808
Bob

[K3LAG]

I just eliminated the trouble codes with my Access Port. It's only function is to makes sure the fuel temperature isn't too high when it runs all the EVAP tests. If you are removing the rest of the EVAP solenoids and sensors, you might as well remove it and program out all of the EVAP associated trouble codes. The only ones I left were for the purge valve on the manifold so I could purge my charcoal canister rather than venting it to fresh air.

[AZPete]

When I got a code I re-connected the temp sensor and taped it to the outside of the tank. Now it's reading the tank temp and I get no code, plus entry #35,667 on the list of uses for duct tape.

[Triathletedave]

When I got a code I re-connected the temp sensor and taped it to the outside of the tank. Now it's reading the tank temp and I get no code, plus entry #35,667 on the list of uses for duct tape.

Since I'm no use at reprogramming the ECU, I was thinking of something like this instead. Plus, I have duct tape!!

Thanks

Dave

[Triathletedave]

Ok, so I put the fuel temp sensor back in, and the related codes no longer show up. Unfortunately, It still will not start. The fuel pump starts up for about a second when the ignition is on, then shuts off right away. It seems to have power, but something is causing it to cut out again. Is there any way to test the fuel pump without pulling it out of the tank again?

[JeromeS13]

Ok, so I put the fuel temp sensor back in, and the related codes no longer show up. Unfortunately, It still will not start. The fuel pump starts up for about a second when the ignition is on, then shuts off right away. It seems to have power, but something is causing it to cut out again. Is there any way to test the fuel pump without pulling it out of the tank again?

Turn on the power and give the ground side a good ground. The OEM fuel pump controller regulates the pump by pulsing the ground signal.

[Triathletedave]

Turn on the power and give the ground side a good ground. The OEM fuel pump controller regulates the pump by pulsing the ground signal.

Is this still true of the normally aspirated engines? I know that the turbo models all have a fuel pump controller (small grey box), but my NA wiring diagram does not show any fuel pump controller, and I have not seen any unidentified modules in my harness that would fit that description either. Wondering if I missed something obvious?

[Bob_n_Cincy]

Hi Dave
My 06 NA wagon did not have the fuel pump controller either. Just a relay to shut if off in case of an accident. or an engine stall.
Bob

[Triathletedave]

Hi Dave
My 06 NA wagon did not have the fuel pump controller either. Just a relay to shut if off in case of an accident. or an engine stall.
Bob

Good to have confirmation. It turns out that 5 litres of fuel was not enough to activate the fuel level sender, and thus the fuel pump shut off immediately to prevent burning up. I put in another 15 litres, and the pump now works fine. Sometimes it is the simplest of things that get in the way. I discovered a small fuel leak on an injector o-ring, but I am now very close to a first start. Getting excited now!

Thanks for all of the help and great advice!

Dave