forester2002s

Yes thicker oil will help to reduce oil leakage. And the loss in fuel economy will be minor.

Could the thumping be from the rear driveshaft? U-joints or bearing? If so, I would expect a difference in thumping when accelerating vs. coasting.

Timing Belt: No matter what the ad says, check the T-Belt before use. Never install an unbranded T-Belt, nor one with confusing or deceptive info on the belt. It's just asking for trouble.

Could it be bad gas? But if you've been experiencing this 'misfire' 'for the past month or so', I would expect that you've had to refill the gas-tank a few times - if so, 'bad gas' would probably not be relevant.

Does the horn work? If not, that might also point to the clock-spring.

I am sure that you know this, but WA can mean 2 places: WA = Washington State USA WA = Western Australia

Are you in Vancouver WA? or Vancouver BC? There would be a big difference in shipping rates + customs declaration etc.

Check that the throttle pedal retracts itself fully when at idle. It is possible that something can physically interact with the pedal, stopping the pedal-spring from doing its job OK. Or the spring itself might be 'tired'.

Check the wheels to see if a balancing-weight has flown-off. You can usually see some marks on the rim, where the missing weight was once located.

On my 2002 EJ2.5, I have to let the engine get cold (I leave it overnight), and I have to wipe the dipstick dry before checking the oil level. That's the only way that I can get a decent reading. On my 2017 FB2.5, if I check it in the morning with the engine cold, the dipstick comes out the first time with a good reading, even without wiping it clean (someone at the Subaru design office has finally figured out how to design a dipstick that works!)

Probably just on the driver's side, since your two problems are on that side.

This sounds like a grounding problem. One bad ground on a single bulb-holder can cause odd problems on other bulbs. Is there any corrosion around any of the bulb-holders? Does the metal body of each bulb-holder measure zero-Ohms to a good ground on the car-body?

Check that the PCV valve is OK.

Make sure the 'new' radio has a good ground.

Perhaps there's nothing wrong with the oil pump. Could this just be a failure of the oil-pressure switch?

Here is some info from the Factory Service Manual for a 2002 Forester (one year later than yours, but may be a similar setup): - Page WI18 Power Supply Routing: on right-side of page is the IGNITION RELAY, which has a 4-pole connector B157 - Page WI119 Bulkhead Wiring Harness (In Compartment): Connector B157 is listed as the IGNITION RELAY 4-pole Red in Zone C-1 - Page WI120 Bulkhead Wiring Harness (In Compartment): Zone C-1 is the location for Connector R157 (misprint for B157?). This view is looking at the main instrument-panel through the open left-side car-door, It appears that the Ignition Relay and the Red connector B157 are way to the left of the steering wheel, and up high, perhaps behind the fuse box. WI14 Power Supply Routing.pdf WI119 Bulkhead Wiring Harness in Compartment.pdf

Here's a possibility: 7 years ago, the timing belt jumped a few teeth, and the car wouldn't run properly, so it was taken off the road and parked. Now 7 years later, the timing is still off, and the fuel is degraded, so it still won't run.

I suspect that the manufacturer's recommendations for oil viscosity have more to do with meeting fuel consumption limits, than other reasons.

Not my car, not my problem (yet). But here's an interesting article about Thermo Control Valves (TCV) on newer Subarus. This link, from the Canadian newspaper The Globe and Mail, is behind a paywall: Costly repairs because of new thermostats will be a growing complaint for drivers . It may not let you in; so I've copied and pasted the text below: LOU'S GARAGE: Thermostats aren’t what they used to be. Gone are the days of the General Motors drop-in style thermostat, where you easily took off a coolant cap, reached down, grabbed a handle, pulled out and replaced an $8 thermostat in 30 seconds. Now, we have complex units referred to as coolant or thermo modules, thermo control valves (TCV) and in many cases, the common contemporary thermostat is only serviceable as a complete unit incorporating a large plastic housing. Owners of European vehicles have tolerated these costly units for at least a decade, but the rest of the automotive world is now becoming painfully aware of this newer tech. These units offer finer temperature control using rotary slide valves that direct coolant flow precisely around the engine and are faster at responding to engine load change. The engine will reach ideal operating temperature 50 per cent faster and keep it there over a wider variety of conditions. Whereas a thermostat is a straightforward valve that merely regulates coolant flow, a TCV can be thought of as a mixing valve. The thermostat is now the coolant gate keeper and the TCV is the director. Case in point is a 2019 Subaru Forester in the shop this week with a Malfunction Indicator Light (MIL) on, no heat inside the cabin and an engine that won’t easily reach operating temperature. This vehicle has a traditional thermostat, but it also has a TCV that has recently failed, leaving this vehicle with no heat. The vehicle has 70,000 kilometres, putting it just outside of its warranty period, thereby passing this costly repair onto a shocked owner. You would be too if you had just received a quote for a $882 part plus a couple hours of labour. Why do we need these units when a simple thermostat has done the job previously with very little fanfare? Well, ever-tightening fuel economy regulations have all auto manufacturers scrambling, looking to squeeze every morsel of mileage out of a litre of fuel. This complicated part does exactly that by elevating fuel economy and reducing CO2 emissions approximately 4 per cent. This may not seem like a lot, but manufacturers have no choice in the matter. This means you have no choice either. The Subaru owner mentioned above is heading in again next week to his local dealer trying to find some financial relief for this repair. In my opinion, 70,000 kilometres seems awful early for such a costly repair to be sprung on an owner, especially when you factor in that up until last week, he had never even heard of a thermo control valve. I suspect this will be a common complaint in years to come for a lot of aging vehicles.

You didn't mention it, so I have to ask: Are there any bubbles in the radiator overflow-tank?

Check the PCV Valve, to see if it's stuck open.

Short-term fix for a dirty PCV valve, if you can't get a new one: - Remove PCV valve; - Fill with solvent, sealing bottom with finger, then finger on top; - Shake well, drain, repeat a few times. This will clean out the PCV valve, and the innards will be freer to move. But replace with new PCV valve ASAP.

The rear hatch has to be properly aligned with the body of the car. If there is any misalignment, the rear striker/latch may not engage fully. When the hatch is closed, the gaps around the perimeter have to be more or less equal (the Factory Service Manual has details). There are 3 adjustment points: - the mounting bolts for each of the 2 upper hinges; - the mounting bolts for the lower striker-bar (hidden under the plastic trim on the sill). I would start with adjusting the lower striker-bar: side-to-side or front-to-back. See what happens.

A side effect is the your speedo will no longer read the correct speed. Larger tires will cause a lower speedo reading.

Yes, but it could be a loose or corroded set of contacts in the ignition-key unit. Maybe you have an intermittent connection, that works sometimes and then cuts out. Next time you have a problem, jiggle the ignition-key and see what happens.