[Al Posts: 1008 Status: Offline WWW]

Thanks John.


I'll certainly be in touch with RJES AS I really don't like electrical stuff.  I don't understand it or the jargon that goes with it and have no intention of learning about it at my age.


I've got the dash panel out, so now about to start removing the electrical stuff under there     I'll just remove everything and put it in a box then hopefully I'll have the bits needed when it come the time to get the loom made.

[John Robertson Posts: 5272 Status: Offline WWW]

If you are talking to RJES then the following needs to be considered (learned after he built a harness for me 4 years ago):

1. You don't need the ECU "ignition key-present" connections from ignition key barrel (they can be permanently shorted together).
2. Fan1/2 control circuits need pull up resistors or the ECU will throw P0480 fault codes (fan1/2 circuit grounded).
3. Engine idle speed can be increased by connecting vent. fan input to gnd and A/C pressure stat input to +12V (around +150rpm or so) - helps compensate for prop/fan load at idle when there should be zero load)
4. Original fuel gauge sender needs connected to ECU or it throws P1422 codes (after continuous running for a couple of hours or so) - it thinks the sender is faulty because the vehicle hasn't used any fuel!   Check for a 2nd fuel sender in the tank (some vehicles have two senders due to tank shape.
5. You'll probably need a VSS (Vehicle Speed Sensor) replacement otherwise the ECU will shut down the engine if it sees above-idle rpm when the vehicle is stationary.

[John Robertson Posts: 5272 Status: Offline WWW]

Will I need to keep the ignition barrel & key?  Reason I ask is that the car is fitted with an immobiliser so not sure how much of that system I can remove.

Yes you need it, and the immobiliser module, and the internal bulkhead wiring harness, and the main relays, etc, etc.  You need to research what's needed for that particular engine/vehicle as Subaru had a habit of changing stuff every few months.  Also look out for a spare ECU and immobiliser (with the same codes) as it's keyed to the immobiliser unit.   The easiest way to get the main engine harness sorted is to go to RJES Engineering - he'll make up a harness from the old one (if you pay him of course!).

And, then, you'll also need a spare sensor set, starter motor and alternator.  The sensors can be found fairly easily (and relatively cheaply once you get the parts numbers) - the easiest (and cheapest) way to get everything is just to get another vehicle!

[Al Posts: 1008 Status: Offline WWW]

Will I need to keep the ignition barrel & key?  Reason I ask is that the car is fitted with an immobiliser so not sure how much of that system I can remove.


Car is a 2006 forester

[Warby Posts: 1045 Status: Offline]

A lot of older engines required zinc in the oil as an anti-ware additive particularly to reduce camshaft/follower ware. This was Zinc Dialkyl Dithiophosphate (ZDDP)
BUT both zinc and phosphorous can damage catalytic converters!!!!!

[John Robertson Posts: 5272 Status: Offline WWW]

Ideally, only get the outside of the sump galvanised (you'll need to talk to the galvaniser about masking).  There is a risk (unknown) that the zinc may contaminate the oil long term (probably not likely as the zinc meltling point is twice that of the hottest oil, although some of the weird oil additives may leach zinc for all I know).

[Al Posts: 1008 Status: Offline WWW]

I expect I'll be picking your brains John, quite a bit with regards the Subaru install.  I had already decided that I will be replacing the sump as there is some corrosion on it, but I hadn't thought about getting it galvanised so that will be going in with the fan & engine frames when I get to that bit.


I found out this morning why the driveshaft had pulled out of the inner joint.  The bottom off side front wishbone had corroded through causing it to break by the front wishbone mounting.  That's quite scary when you think about it, especially on a car that was Mot'd and up to date service history.  Don't think I'll take my car to the garage that has serviced the car the past couple of times. 

[John Robertson Posts: 5272 Status: Offline WWW]

If it's not directly controlled by the ECU (i.e. there is a relay) then leaving the relay connected should be enough for the ECU fault scan (it can't know if the pump is there OR working if it's only used at startup as the O2 sensors won't be warmed up yet).

There is plenty of stuff that can be removed from these engines - tank vapour vent valve and pipework (leave the valve body to keep the ECU happy but remove all pipework),  the injector swirl valve and pipework (again, leave the valve solenoid and remove all pipework), replace all of the under-manifold rust-prone metal pipes (fuel, etc.) with 3x EN7840 grade hose, remove the heavy injector covers.  And, lastly, buy a new sump and get it galvanised along with the other bits - the existing sump, probably already corroded, won't last long in a salt water environment.

Air injection is very old-tech - I've got a 50 year old car that uses it!

[Al Posts: 1008 Status: Offline WWW]

Thanks Warby.


Now I know what it is, I was able to find it in the Haynes manual 


Typical, only fitted to 2006 forester models and later turbo models.  I always seem to make things more complicated than they need to be  [size=78%] [/size]

[Warby Posts: 1045 Status: Offline]

Its a "Secondary Air Pump" to reduce emissions on start up.
Secondary air injection systems pump outside air into the exhaust stream so unburned fuel can be burned. Only runs for a minute or two after start up. It can be discarded BUT Engine ECU Management system may show a fault and the exhaust will require blanking off where air is injected. ECU may need a re-map so fault codes aren't displayed.
Also if exhaust gas recirculation is fitted better to discard. Less to go wrong!!!!!!!!!!

[Al Posts: 1008 Status: Offline WWW]

Mine is naturally aspirated, but I found a picture online showing the denso unit bolted to the n/s suspension strut behind the battery, which may help to identify it.


2006 subaru forester engine breathing - Bing images

[Al Posts: 1008 Status: Offline WWW]

Here's one for the mechanics on here.


What is it?


Do I need it?


Subaru forester 2006 naturally aspirated EJ20 engine.


I have  Haynes manual, but can't see any pictures so aven't a clue what it is.


It attaches to the engine breather.