The 'Black Socket Trick'

Machines that read fault-codes aren't cheap, starting at about £350 and running into thousands for a pro one, so its good to know that Subaru, like a lot of other Japanese marques, builds in a gizmo that lets us check the codes ourselves, at the roadside if we need to.

There is a male and female plastic connector hanging loose just behind the trim under the steering column, just behind where the socket for the OBD-type reader is. The connectors are unplugged from each other by default and clipping them together bypasses the circuit for the OBD socket so the car's own can be used.

Once the two connectors are clipped together, turn the key so the ignition is fully on, without starting the engine. The CHECK ENGINE light will do a series of long and short flashes. First come the long flashes [about 1 sec each], which denote the first digit of the fault-code and then quick flashes, which denote the second digit. i.e two long and three short would be a fault-code 23.

Here is the LIST OF FAULT CODES that work with the system.

[The car still works with the connectors left plugged in, but its probably best to unplug them to save the car doing a check every time you start up and make the OBD socket accessible if you take the car in to a garage. Not that any ScoobyLab fan should ever have to!]

What Turbo?

If your turbo is on its way out then you might not know which one to buy. This guide from BTN Turbos might come in handy. BTN can also supply identical replacement turbos [here http://www.btnturbo.com], but the prices can be astronomical so a cheaper OEM-spec alternative from eBay etc. is probably a better bet.

Engine	Trim	BHP	Engine Code	Year	OEM Part	Turbo Make / Model
2.0 P		--	41T	-	14411-AA562	Mitsubishi TD04
2.0 P		--	--	-	14411-AA620	IHI RHF55
2.0 P		--	--	1996 -	14411-AA173	IHI RHF5HB
2.0 P		--	58T / EJ205	1998 - 2003	14412-AA140	Mitsubishi TD04
2.0 P		--	--	2003 -	14411-AA542	IHI RHF5
2.0 P		210	58T	1997 -	14412-AA092	Mitsubishi TD05
2.0 P	GT	218	--	1997 -	14411-AA202	IHI RHF5HB
2.0 P	WRX-NB	246	EJ205	2000 -	14411-AA383	Mitsubishi TD04
2.0 P	WRX R8	280	--	1996 -	14411-AA220	IHI RHF5HB
2.5 P	WRX	--	--	2001 -	14411-AA321	IHI RHF5
2.5 P	2.5i WRX	280	--	2000 -	14411-AA373	IHI RHF5
2.5 P	2.5i WRX	280	--	2001 -	14411-AA44	IHI RHF55

Apparently our MY98 would take a Mitsubishi TD-04 turbo, which is kind of ironic seeing as they make the Lan EVO, but wouldn't have this turbo anywhere near it.

Suspension Upgrade Help

Uprated Springs / Dampers

Fitting sport-springs will stiffen up the ride and lower the car, but the Scoob's standard dampers are Kayaba Racing jobs so its not worth shelling out a couple of hundred for an uprated damper set as well because they won't give a worthwhile improvement to handling at all, unless you're standard shocks are knackered. If you just want to lower the Impreza then go for a spring-set only, it's a lot cheaper. If you're trying to stiffen up the handling then coilovers, below, are the only way to getting round corners quicker and flatter.

Coilovers

These replace both the spring and damper with a much stiffer, tougher and more compact unit, which is designed for handling first, comfort last, so road-holding gets a significant boost. They're also completely height-adjustable, so you change them from road to track in a few minutes and higher-end models also have settings for castor/camber angle and a greater degree of control.

Strut Brace

A strut-brace is a stiff bar that bolts across your suspension turrets and stiffens the whole chassis up. Front ones are an essential. Rear strut-braces are only necessary on Wagon Imprezas, saloon and coupe models have an integral one built-in. They're not an expensive mod, but the difference they make is amazing so if you're after better cornering then fit one right now. Price-wise, a good generic-brand one, like Sparco or OMP, is about £90. A proper JDM one, like TEIN or Cusco, will be £200+. If price is a worry then you can find pretty good looking no-make alloy ones on eBay for £50 or less, but I'd recommend scanning the auctions for a 2nd-hand STi one, fitted to the Ver. 3 and up. This is made of titanium with carbon-fibre rods, so its lighter than the rest and looks amazing. They seem to hang in the £50-100 range - I got mine for £65.

Drop Links / Anti-Roll Bar Links

These bolt between the hub and the anti-roll bar on either side to stop the car swaying like a boat. Standard ones are pretty stiff, but designed to give a little in the aid of comfort. Uprated ones have no give at all and will keep the car flat through bends. A good set of alloy drop-links with poly-bush inserts start at about £50 a pair on eBay. Handling will be firmer and steering ultra-responsive, but there'll be a lot more vibration and road noise.

Poly-Bushes

Upgrading these things is for serious nutters and trackday-special cars only really. Rubber-bushes are designed to have a little bit of play in them to soften the ride up, but they deteriorate over time and if your'e working on a classic Scooby then the chances are the bushes are quite worn and there'll be a bit more play in the chassis. Upgrading them to much stiffer and harder-wearing polyurethane ones [or 'poly-bushes'] means there's no play in the chassis whatsoever, which is great for staying flat as a pancake round that tough right-hander, but finally makes nipping to Tescos or pleasant day trips out of the question. The car will jar and bounce over every pebble on the road, but if day-to-day drivability is not your concern then this is the final rung on the ladder to real race-car suspension.

Rear-Wheel Drive Conversion

This would be another ultimate modification. I know it may seem silly to rob the Scoob of its famous 4WD, but it would make for one unique Impreza and is an essential requirement if you want to build a serious drift car. The basics to do it are already there - power already goes to the rear and it has a limited-slip diff. - so I guess the only job would be to cut off the front wheels in a way that didn't mess up the centre-differential, or even replacing the centre diff. altogether.

I'll be looking into this soon.

Impreza Model Indentification

Classic:

Classic 1 - 1993 - 1997 (Ver. 1, 2 STi)

2-bar grille in the bumper corners, slatted bonnet-vents.

Classic 2 - 1997 - early 1998 (Ver. 3, 4 STi)

Grille update, bigger scoop and mesh-look bonnet-vents.

Classic 3 - late 1998 - early 2001 (Ver. 5, 6 STi)

Deeper grille, new '22B/P1' style front-bumper with

'crystal' clear spotlights and one-bar bumper-corner grilles.

New Age:

Bugeye - late 2001 - 2003 (Rev. A,B,C STi)

New chassis and body, round headlights.

Blobeye - 2004 - 2005 (Rev. D,E STi)

New front bumper/grille, large twin headlight-clusters.

Hawkeye - 2006 - 2007 (Rev. F,G STi)

New front bumper/grille, angular tapering headlight-clusters.

3rd Gen:

Hatchback - 2008 onwards

Subaru Workshop Manuals

With no Hayne's manual available for the Impreza, service and repair jobs might seem a bit out of reach to the home mechanic, so I've tracked down some Service and Workshop manuals, Subaru's own, on a great site called PDFTown. Links below:

MY97-98 Subaru Service Manual - http://pdftown.com/PDF-Subaru-Impreza-1997-1998-Service-Manual.html

I cant find a more detailed Subaru workshop manual for my MY98 car, but there is one for MY99-00 cars and most of the parts and fitting are still identical - http://pdftown.com/Subaru-Impreza-1999-2000-Workshop-Manual.html

All other Subaru manuals are here - http://pdftown.com/Pdf-eBook/Subaru.html

Subaru Specific Fault Codes

Here's a list of the fault-codes that correspond the 'Check Engine' flashes from the 'Black-Socket Trick'. The number of long flashes represent the first digit of the code and the short flashes are the second digit, i.e 2 long flashes and 3 short would be a code 23.

[If you have a plug-in module for reading OBDII fault-codes then you'll need this set of codes instead - generic Subaru OBDII trouble code definitions - from ScoobyPedia.]

1	Engine Speed Signal Circuit
11	Crankshaft Position Sensor
12	Starter Signal
13	Camshaft Position Sensor
14	Fuel Injector No. 1 (Legacy, Impreza, Justy, SVX)
15	Fuel Injector No. 2 (Legacy, Impreza, Justy, SVX)
16	Fuel Injector No. 3 (Legacy, Impreza, Justy, SVX)
17	Fuel Injector No. 4 (Legacy, Impreza, SVX)
18	Fuel Injector No. 5 (SVX)
19	Fuel Injector No. 6 (SVX)
21	Engine Coolant Temperature Sensor
22	Knock Sensor
23	Mass Air Flow Sensor Circuit
24	Idle Control System Malfunction
24	ISC Valve (Stick)
24	Open/Short in ISC Valve Circuit
26	Intake Air Temperature Sensor
27	ATF Temperature Sensor Circuit
28	Knock Sensor #2
29	Crankshaft Position Sensor 2
31	Throttle Position Sensor Circuit
32	A/F Sensor #1 System
32	A/F Sensor #2 System
32	Oxygen Sensor
33	Vehicle Speed Sensor
35	CPC System
36	Turbine Speed Signal
37	Rear O2 Sensor Circuit / A/F Sensor Circuit Malfunction
38	Torque Control Signal #1
38	Torque Control Signal #2
38	Torque Control Signal System
38	Torque Permission Signal
39	Traction Control System
41	Air/Fuel Adaptive Control
42	Idle Switch
43	Accelerator Pedal Switch
44	Turbocharging Pressure Control Signal
45	Pressure Sensor
46	Neutral or Parking Switch or Circuit
47	Fuel Injector
48	Lean Burn System
49	CO Resistor
51	Neutral Position Switch
52	Parking Brake Switch (Exc. Justy)
53	Antenna
53	Anti-Quick Operation Mode
53	Communication Error (Time Over)
53	EGI Control Module EEPROM
53	IMM Circuit Failure (Except Antenna Circuit)
53	IMM Control Module EEPROM
53	Key Communication Failure
53	Reference Code Incompatibility
53	Use of Unregistered Key
54	Air Intake System
55	EGR Valve Lift Sensor
56	EGR System
57	Canister Control System
58	Air Control System
61	Air Suction Control Solenoid Valve
62	Exhaust Manifold Valve Negative Pressure Control Solenoid
64	Relief Valve Control Solenoid Valve 1
64	Relief Valve Control Solenoid Valve 2
65	Differential Pressure Sensor
66	Twin Turbocharger System(H)
66	Twin Turbocharger System(S)
66	Twin Turbocharger System(T)
66	Two Stage Twin Turbocharger System
67	Exhaust Manifold Valve Positive Pressure Control Solenoid
68	Turbocharging Pressure Control Output Signal #2
71	Shift Solenoid Valve
72	Shift Solenoid #2 Circuit
73	Low Clutch Timing Solenoid Circuit
74	Brake Clutch Timing Solenoid Circuit Malfunction
75	Line Pressure Duty Solenoid Circuit
76	Brake Clutch Pressure Duty Solenoid Circuit Malfunction
77	Lock-Up Duty Solenoid Circuit
78	Tiptronic Solenoid System
79	Transfer Clutch Duty Solenoid Circuit
81	Torque Up Control Valve
85	Charger System Circuit Malfunction
86	CAN (Communication System)
87	Variable Induction Solenoid Valve Circuit Malfunction
88	Fuel Pump Circuit Malfunction
89	VVT Systems (L)
89	VVT Systems ®
91	TCS Relief Valve
92	Electrical Generation Control Signal Circuit Malfunction
93	Vehicle Speed Sensor #1 Circuit
94	Lateral G Sensor Signal Circuit Malfunction

Impreza Model Timeline

Here is a reasonably accurate timeline of all the model updates and special announcements made to the Impreza range. The information here is borrowed from the Impreza Web Owners Club [http://www.iwoc.co.uk/], which is an amazing database of all things Scooby. The information has been added to the timeline since the late nineties, but stops at 2004, so I will try to fill in the blanks that follow eventually.

Eta Tauri Impreza Reference

Impreza Chronology

1992 November

The Impreza is released in Japan.

1993

The Impreza is released in the UK. Initially only the 5 door was made available with the 4 door available later. Both 4 wheel and 2 wheel drive drive with 1.6, 1.8 and 2 litre engine options.

1994

The Turbo is released in the UK.

1995 June

First UK special edition released. The McRae was only available in deep blue with 16 inch Speedline Safari alloys, Recaro interior and factory fitted sunroof. Only 200 off produced to celebrate Colin McRae winning the World Rally Championship for Subaru.

1995 October

The 2 wheel drive and the 1.6 and 1.8 litre models are dropped from the line up.

1996 October

Facelift body with a more aggressive nose and headlights. The bonnet is resculptured and the bonnet vents either side of the scoop revised. Engine modifications decrease turbo lag and increase torque by using a smaller turbocharger and a straighter inlet path. Power remains the same.

First STi 2 door coupe. 294mm diameter disc brakes and 4 pot calipers seen for the first time on the STi models.

1997 April

Second UK special edition released. The Catalunya was only available in black with gold wheels with black and red interior and air con as standard. Only 200 off produced to celebrate winning the Catalunyan Rally and the Manufacturer World Rally Championship in 1996

1997 October

Revised interior using the Forester dash board, Momo steeing wheel and twin airbags. Switchgear and paneling changed on the doors also. Exterior was limited to an upgrade to 16in alloys.

Japanese STi models (version 4) see medium level spoiler.

1998 April

Third UK special edition released. The Terzo was only available in Sonic Blue with gold wheels with Alcantara trimmed seats and interior with air con as standard. Only 333 off produced to celebrate the third consecutive win of the Manufacturer World Rally Championship.

Japanese release a wide bodied rally replica 2 door coupe with a 2.2 litre turbo charged engine. The 22B was only available in Sonic Blue with wide 235x40x17 gold alloys, high level rear spoiler and revised front nose and bonnet. Only 400 off where produced for the Japanese market to celebrate 40th anniversary of Subaru.

1998 October

Revised front bumper similar in looks to the 22B and medium level spoiler at rear. Power has increased from 208 to 211bhp and brakes have improved with dual twin opposed pot calipers from the STi models.

22B-UK announced at the NEC Motorshow. Only 16 off to be imported, with conversion to UK specification by Prodrive.

Japanese STi models (version 5) have a high rear spoiler as standard. Suspension is revised with "upside down" dampers.

1999 April

Fourth UK special edition released. The RB5, only available in Blue Steel Metalic with special graphite coloured Speedline 17in alloys, Alcantara trim and air con as standard. Only 444 off produced to celebrate Richard Burns joining the Subaru WRC Team. The RB5 was also available as an RB5-WR with Prodrive high level spoiler and performance pack.

1999 October

Revised interior, new 16in alloys and colour coding of mirrors, and door handles.

P1 announced at the London Motorshow. 1000 off 278bhp 2 door coupes to be imported with full European Whole Vehicle Approval. Only available in Sonic Blue with suspension and body styling by Prodrive.

Japanese STi models (version 6) have high level spoiler, some double wing bi-plane style! New alloys also seen on some of the models.

2000 May

Special editon of the 2 litre Sport model. Available in either Canary Yellow, or Mica Black with matching interior trim and external bodywork to Turbo specification.

2000 September

New Age Impreza seen for the first time in Japan.

2000 October

Worldwide launch of the New Age Impreza. Three models to be introduced in the the UK - WRX 2 litre turbo, GX 2 litre and TS 1.6 litre. Both WRX and GX available in 4 and 5 door, the TS only 5 door.

Japanese STi seen for the first time in Japan.

2001 February

The WRX is released for the first time in the USA and Canada as the MY2002.

2001 May

First UK special edition of the New Age Impreza released. The UK300, only available in Rally Blue Metalic with gold 18in alloys, Prodrive front and rear spoilers, modified headlights and Alcantara trim as standard. Only 300 off produced. Available as an option on the UK300, this marked the first release of the Prodrive performance pack for the MY2001.

2001 September

European STi announced at the Frankfurt Motorshow along with an enhanced Prodrive Style model. In Japan the MY2002 WRX, STi8, and Prodrive Style announced all being lightly different to the Euro versions.

2002 May

Subaru releases a number of limited editions in Japan to celebrate their 30th anniversary. Amongst these are the S202, the first Impreza to officially break the gentlemans agreed 280PS. Also released is an STi with 384N-m of torque (more than a 22B)!

2002 July

Subaru UK release the Impreza 2 litre GX Sport Special Edition featuring Morrettes headlamps and high rear spoiler for the same price as the standard GX model.

2002 September

Facelift MY2003 unvieled at the Paris Motorshow. The car features a complete windscreen forward make over and the Bug Eye headlights are no more. The rear sees Lexus style light clusters and on the STi a high rear spoiler as standard. Power on the standard WRX version is up to 225PS from 215PS but there are no changes to the 265PS STi.

2003 December

To celebrate winning the WRC, Japan announces Petter Solberg Special Edition in both STi and WRX format. Available in rally blue the STi is a limited number of vehicles upto 555 in total, each individually numbered. The WRX is also a special edition but the vehicles only carry the V-Limited plate and are not individually numbered.

2004 January

Subaru UK release the WR1, a special edition STi featuring DCCD-A, Prodrive Performance Pack as standard, Speedline alloys, driving lights, mesh grills and Ice Blue metallic paint.

Good Part Sources

This is a thread I'm starting of good places to get cheap and hard to find parts from, as well as some good businesses on eBay.

Subaru doesn't really have a chain of dealerships and service centres. Instead it uses a few private garages already specialising in Scoobys, who will source parts directly from manufacturer. These places are approved by Subaru Japan, but they can cost a bomb, both parts and labour. Either way here is the Subaru dealer locator - http://subaru.co.uk/dealer-locator/

Flat 4 Online - http://www.flat4online.co.uk/ - Endless catalogue of Scooby replacement parts and upgrades.

Import Car Parts - http://importcarparts.co.uk/ - Great site for finding small and rarer replacement parts like bushes and clips. Can also be found on eBay [http://stores.ebay.co.uk/Import-Car-Parts-Japanese-Car-Parts], with parts often cheaper than the website!

MAF Label Colour Guide

MY97/98 UK/Euro - Purple Label

MY97/98 Japan - Orange Label

Will finish soon!