Category Archives: EJ257

JDM Automatic Intercooler STi Switch Install:

JDM Automatic Intercooler STi Switch Install:

Here is the step by step guide to installing the JDM Automatic Intercooler STi switch. For those of you wondering the advantage of upgrading to the JDM automatic intercooler switch is that it essentially works as a on/off switch for the STi intercooler sprayer. So there is no more constant pushing of the sprayer button. Push the button once to turn it on, and again to turn it off. However, it will empty out your intercooler sprayer tank very quickly if you keep it on.

Here is the switch we are going to be installed:

JDM Automatic Intercooler Switch: The JDM intercooler switch that you will be installing.
JDM Automatic Intercooler Switch: The JDM intercooler switch that you will be installing.

1.) Pop out the fuse box panel. The fuse box panel is located underneath and to the left of the steering wheel.

2.) Use your fingers to depress the tab on the button of the button to pop it out.

JDM Automatic Intercooler Switch: The USDM stock STi switch that you will be removing.
JDM Automatic Intercooler Switch: The USDM stock STi switch that you will be removing.

3.) Pull the switch out of the dash.

4.) Depress the tab on the back of the plug to remove the switch.

JDM Automatic Intercooler Switch: USDM STi intercooler switch removed. Get ready to install the JDM switch now.
JDM Automatic Intercooler Switch: USDM STi intercooler switch removed. Get ready to install the JDM switch now.

Oil Additives: What Subaru Says

Oil Additives: What Subaru Says

Subaru of America does not recommend the use of any engine oil additives in any Subaru engine crankcase. Subaru engines are designed to be lubricated with normal petroleum or synthetic-based engine oils in the viscosity and grade indicated in the Owner’s Manual for each specific engine and usage condition. Subaru has not tested the effectiveness or compatibility of any engine oil additives.

Oil Additive: Avoid adding any oil additives to your Subaru boxer engine.
Oil Additive: Avoid adding any oil additives to your Subaru boxer engine.

However, the use of such oil additives does not void warranty coverage. Usage of any additive is at the owner’s discretion. Since Subaru has not tested the compatibility or effectiveness of any such additives, should an engine failure occur that is determined to be caused by the incompatibility or performance of such an additive, the vehicle owner would be be referred to the additive manufacturer to request reimbursement of the cost of the repair.

If you are using oil additives to try to save a leaking headgasket it’s better to just suck it up and just either install new headgaskets yourself or have the work done by a trusted mechanic.

Either use Subaru’s OEM synthetic motor oil or use Rotella T6 motor oil. If your Subaru is still under warranty by Subaru it’s best to get your oil changed by a Subaru dealership and avoid introducing oil additives into your boxer engine. Even if it’s Subaru’s official stance that they won’t void warranties if oil additives are involved it doesn’t mean that they won’t if there is more evidence of engine “tampering”. Avoid anything that could potentially cause a dealership to refuse service to your car in the future.

Otherwise you might have a expensive repair bill if your Subaru boxer engine spins a bearing or has a ringland failure. Of course adding aftermarket parts like an exhaust or intake along with a tune will greatly increase the justification of a Subaru dealership to void a warranty more than adding oil additives.

Not adding oil additives can be another step in avoiding a void warranty from Subaru of America. On a final note remember that Subaru can scan your ECU for previous tunes even if you went back to a stock tune and will void a warranty for that.

Maintenance:Subaru Periodic Maintenance Part 1:

Maintenance: Subaru Periodic Vehicle Maintenance Services:

Vehicle maintenance is an important factor for proper vehicle operation. It’s the vehicle owner’s responsibility to ensure that fluid levels (engine oil, coolant, etc.) are checked frequently, in accordance with the instructions in the Subaru owner’s manual. However, many ‘gas and go’ vehicle owners may not take the time to fulfill these basic responsibilities. This places added importance on the performance of periodic maintenance services. If the Subaru owner isn’t looking after his vehicle, it falls to the automotive service professional to ensure that proper maintenance procedures are performed.

Maintenance: Subaru Periodic Vehicle Maintenance: It's always important to periodically check your Subaru's timing belt for wear and tear.
Maintenance: Subaru Periodic Vehicle Maintenance: It’s always important to periodically check your Subaru’s timing belt for wear and tear.

The frequency of scheduled inspection and maintenance services required by late model Subaru vehicles is minimal when compared with vehicles of the past. For example, even the very commonly used term ‘tune-up’ has lost most of its original meaning. In the old days, a ‘tune-up’ meant fresh spark plugs, points and condenser, and basic engine adjustments such as timing, idle mixture and idle speed. Modern technology has eliminated the need for many of these adjustments and replacement parts. However, the tune-up is alive and well— only its definition has changed.

While the number of vehicle items requiring regular replacement has decreased, the number of items needing periodic inspection has not. Whether you call it a tune-up or something else, this service offers an excellent opportunity for all engine belts, hoses and ignition wires to be checked for wear and tension. Old tune-up standbys like spark plugs, fuel and air filters are still on every Subaru vehicle and still require periodic inspection and replacement as necessary.

The same applies to all other items on the Subaru maintenance schedule. The important thing is to carefully inspect each item. If additional corrective action is required, now is the time to find out.

Subaru OBD-2 Diagnostic Trouble Codes:

Subaru OBD-2 Diagnostic Trouble Codes:

This is a list of the OBD-2 diagnostic trouble codes for Subaru Impreza, WRX, STi, Forester, and Legacy.

Subaru OBD2 Diagnostic port
Subaru OBD2 Diagnostic port

P0031 Front oxygen (A/F) sensor heater circuit low input
P0032 Front oxygen (A/F) sensor heater circult high input
P0037 Rear oxygen sensor heater circuit malfunction
P0038 Rear oxygen sensor heater circuit high input
P0065 Air assist injector solenoid valve malfunction
P0066 Air assist injector solenoid valve circuit low input
P0067 Air assist injector solenoid valve circuit high input
P0100 Mass or Volume Air Flow Circuit Malfunction
P0101 Mass or Volume Air Flow Circuit Range/Performance Problem
P0102 Mass or Volume Air Flow Circuit Low Input
P0103 Mass or Volume Air Flow Circuit High Input
P0104 Mass or Volume Air Flow Circuit Intermittent
P0105 Manifold Absolute Pressure/Barometric Pressure Circuit Malfunction
P0106 Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance Problem
P0107 Manifold Absolute Pressure/Barometric Pressure Circuit Low Input
P0108 Manifold Absolute Pressure/Barometric Pressure Circuit High Input
P0109 Manifold Absolute Pressure/Barometric Pressure Circuit Intermittent
P0109 Intake Air Temperature Circuit Malfunction
P0111 Intake Air Temperature Circuit Range/Performance Problem
P0112 Intake Air Temperature Circuit Low Input
P0113 Intake Air Temperature Circuit High Input
P0114 Intake Air Temperature Circuit Intermittent
P0115 Engine Coolant Temperature Circuit Malfunction
P0116 Engine Coolant Temperature Circuit Range/Performance Problem
P0117 Engine Coolant Temperature Circuit Low Input
P0118 Engine Coolant Temperature Circuit High Input
P0119 Engine Coolant Temperature Circuit Intermittent
P0120 Throttle/Petal Position Sensor/Switch A Circuit Malfunction
P0121 Throttle/Petal Position Sensor/Switch A Circuit Range/Performance Problem
P0122 Throttle/Petal Position Sensor/Switch A Circuit Low Input
P0123 Throttle/Petal Position Sensor/Switch A Circuit High Input
P0124 Throttle/Petal Position Sensor/Switch A Circuit Intermittent
P0125 Insufficient Coolant Temperature for Closed Loop Fuel Control
P0126 Insufficient Coolant Temperature for Stable Operation
P0128 Thermostat malfunction
P0130 O2 Sensor Circuit Malfunction (Bank 1 Sensor 1)
P0131 O2 Sensor Circuit Low Voltage (Bank 1 Sensor 1)
P0132 O2 Sensor Circuit High Voltage (Bank 1 Sensor 1)

P0133 O2 Sensor Circuit Slow Response (Bank 1 Sensor 1)

P0134 O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
P0135 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
P0136 O2 Sensor Circuit Malfunction (Bank 1 Sensor 2)
P0137 O2 Sensor Circuit Low Voltage (Bank 1 Sensor 2)
P0138 O2 Sensor Circuit High Voltage (Bank 1 Sensor 2)
P0139 O2 Sensor Circuit Slow Response (Bank 1 Sensor 2)
P0140 O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 2)
P0141 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0142 O2 Sensor Circuit Malfunction (Bank 1 Sensor 3)
P0143 O2 Sensor Circuit Low Voltage (Bank 1 Sensor 3)
P0144 O2 Sensor Circuit High Voltage (Bank 1 Sensor 3)
P0145 O2 Sensor Circuit Slow Response (Bank 1 Sensor 3)
P0146 O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 3)
P0147 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 3)
P0150 O2 Sensor Circuit Malfunction (Bank 2 Sensor 1)
P0151 O2 Sensor Circuit Low Voltage (Bank 2 Sensor 1)
P0152 O2 Sensor Circuit High Voltage (Bank 2 Sensor 1)
P0153 O2 Sensor Circuit Slow Response (Bank 2 Sensor 1)
P0154 O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 1)
P0155 O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1)
P0156 O2 Sensor Circuit Malfunction (Bank 2 Sensor 2)
P0157 O2 Sensor Circuit Low Voltage (Bank 2 Sensor 2)
P0158 O2 Sensor Circuit High Voltage (Bank 2 Sensor 2)
P0159 O2 Sensor Circuit Slow Response (Bank 2 Sensor 2)
P0160 O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 2)
P0161 O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
P0162 O2 Sensor Circuit Malfunction (Bank 2 Sensor 3)
P0163 O2 Sensor Circuit Low Voltage (Bank 2 Sensor 3)
P0164 O2 Sensor Circuit High Voltage (Bank 2 Sensor 3)

P0165 O2 Sensor Circuit Slow Response (Bank 2 Sensor 3)
P0166 O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 3)
P0167 O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 3)
P0170 Fuel Trim Malfunction (Bank 1)
P0171 System too Lean (Bank 1)
P0172 System too Rich (Bank 1)
P0173 Fuel Trim Malfunction (Bank 2)
P0174 System too Lean (Bank 2)
P0175 System too Rich (Bank 2)
P0176 Fuel Composition Sensor Circuit Malfunction
P0177 Fuel Composition Sensor Circuit Range/Performance
P0178 Fuel Composition Sensor Circuit Low Input
P0179 Fuel Composition Sensor Circuit High Input
P0180 Fuel Temperature Sensor A Circuit Malfunction
P0181 Fuel Temperature Sensor A Circuit Range/Performance

P0182 Fuel Temperature Sensor A Circuit Low Input
P0183 Fuel Temperature Sensor A Circuit High Input
P0184 Fuel Temperature Sensor A Circuit Intermittent
P0185 Fuel Temperature Sensor B Circuit Malfunction
P0186 Fuel Temperature Sensor B Circuit Range/Performance
P0187 Fuel Temperature Sensor B Circuit Low Input
P0188 Fuel Temperature Sensor B Circuit High Input
P0189 Fuel Temperature Sensor B Circuit Intermittent
P0190 Fuel Rail Pressure Sensor Circuit Malfunction
P0191 Fuel Rail Pressure Sensor Circuit Range/Performance
P0192 Fuel Rail Pressure Sensor Circuit Low Input
P0193 Fuel Rail Pressure Sensor Circuit High Input
P0194 Fuel Rail Pressure Sensor Circuit Intermittent
P0195 Engine Oil Temperature Sensor Malfunction
P0196 Engine Oil Temperature Sensor Range/Performance
P0197 Engine Oil Temperature Sensor Low
P0198 Engine Oil Temperature Sensor High
P0199 Engine Oil Temperature Sensor Intermittent

Valve Cover Gasket replacement Subaru WRX:

Valve Cover Gasket replacement Subaru WRX:

This is a step by step guide on replacing the valve cover gasket on Subaru flat four engines. This guide will work for most Subaru turbo cars 02-07+ and most other naturally aspirated Subaru cars.

1.) Jack your car up and drain the oil. Remember to put the car on jack stands. You don’t want the car dropping on you.A lot of people do this job with the oil still in the pan, but its better to rather play it safe and drain the oil completely.

2.) Remove the front air scoop. It takes two 10mm bolts.

3.) Remove the nice Cold Air intake box.

4.) After removing all that, you should see this a total of 8 outer bolts and the 2 inner which holds the spark plug coils.

Valve cover gasket: In the center are the two coil packs that need to be removed.
Valve cover gasket: In the center are the two coil packs that need to be removed.

5.) Unscrew them and label them. You don’t want the bolts going into the wrong place. It was a very hard to get any decent clearance so take your time.

Intake manifold bolts loose on a Subaru STi:

Intake manifold bolts loose on a Subaru STi:

Don’t forget to tighten down your intake manifold bolts down to the correct torque values.

Intake manifold bolts loose on a Subaru STi: Make sure to tighten down your intake manifold bolts.
Intake manifold Subaru STi: Make sure to tighten down the bolts.

 

Otherwise you’ll end up with a broken sounding engine like this:

Luckily forgetting to tighten down the intake manifold bolts didn’t cause any permanent damage, but I wouldn’t go driving around like this either.

If you do TGV deletes like in this post. Make sure to use new intake gaskets where the TGV’s and the intake manifold meet up. What’s even more important is to make sure you tighten down those intake manifold bolts that hold the intake manifold to the TGV’s.

Oil pan removal and install on Subaru STi/WRX:

Oil pan removal Subaru STi/WRX:

This is a step by step guide on removing and re-installing a oil pan on your Subaru Impreza STi or WRX. This guide is also useful for installing a STi spec oil pan onto your WRX. This guide also is helpful if you are removing your stock oil pickup tube that is known to crack on the STi. I suggest purchasing a Killer B Motorsport Pickup Tube along with a brand new STi oil pan. Both can be purchased from down below from Amazon.

Brand new STi oil pan:

Subaru 11109AA131 Oil Pan

Killer B Motorsport Pickup Tube:

Killer B Motorsport Subaru Oil Pan Pickup Tube for EJ25 WRX/STI

 

Oil Pan Removal Steps:

1) Remove the plastic under tray from your engine. This is secured using a few bolts and plastic push clips.

2) Remove the plastic under trays from either side of the car, the long ones.

Oil pan removal and install: Remove plastic to gain access to the bottom of the engine.
Oil pan removal and install: Remove plastic to gain access to the bottom of the engine.

3) Remove the jacking plate. This is held on by 2 12mm bolts with nuts in the front, 2 12mm bolts in the rear and 4 14mm nuts on the sides.

4) Remove your subframe. This is secured by a few 19mm bolts, 2 12mm bolts in front and 4 14mm bolts. I highly recommend soaking these all in your PB blaster and waiting 5 minutes. Check out some of my other posts for instuctions.

5) Remove the front oxygen sensor. The correct way is to unplug the clip, unhook it from the metal mount and then pull the wire through the fender-well so that the wire isn’t being stretched and twisted as you unscrew it.

O2 sensor location in the exhaust manifold.
O2 sensor location in the exhaust manifold.

Sway bar (front) and endlinks install on GD STi:

Front sway bar and endlinks install on 02-07 STi:

This is a step by step guide in installing a front sway bar with aftermarket endlinks on a 04-07 Subaru STi.

1.) Get the car in the air and be sure to secure the car. I used jack stands in the cutouts on the side of the car’s lower frame. It may be easier to use ramps since you will need to tighten the sway bar mounting bolts when the suspension is “loaded,” that is when the full weight of the car is on the wheels/tires.

2.) Remove the front lower cover (splash guard). There are five bolts that require a 12 mm socket, three in the front and two toward the rear. There are two pop fasteners on each side as well. These can be removed by using a small flat bladed screwdriver to pop up the center round plastic piece about a quarter of an inch then pulling/wriggling out the entire fastener.

3.) Remove the jack plate. There are four bolts in the center area to remove and two nuts on each side.

Front sway bar and endlinks: Remove splash guard and skid plate.
Front sway bar and endlinks: Remove splash guard and skid plate.

4.) The sub-frame is an odd looking, approximately C shaped, bracket under the front part of the car. The opening of the C is toward the rear of the car. It helps to remove this to make it easier to get to the bolts that hold the sway bar onto the frame.

The sub-frame has five bolts on each leg of the C and two toward the front of the car. The two rearmost bolts require a 14mm socket, the other three on each side require a 17mm socket and the two on the front require a 12mm socket. Start by removing a plastic cover on each side that is held in place by two pop fasteners.

Front sway bar and endlinks install on 02-07 STi: The sub-frame is an odd looking, approximately C shaped, bracket under the front part of the car. The opening of the C is toward the rear of the car. It helps to remove this to make it easier to get to the bolts that hold the sway bar onto the frame.
Front sway bar and endlinks install on 02-07 STi: The sub-frame is an odd looking, approximately C shaped, bracket under the front part of the car. The opening of the C is toward the rear of the car. It helps to remove this to make it easier to get to the bolts that hold the sway bar onto the frame.

5.) Remove another pop fastener on each side of the sub-frame.