Subaru Impreza Engine Problems

The smell you're describing has been around since 1986 when all new cars sold in Australia were forced to use unleaded petrol. That move was to protect the catalytic converters fitted from that date (leaded fuel would have damaged them) and the combination of these converters and the new fuel resulted in the smell you're noticing. So it's not new, but it does vary from car to car and possibly even from one brand of fuel to another.

It's supposed to be harmless to humans, but if you can smell it, that automatically means you're being exposed to other chemicals in the car's exhaust emissions, including various carcinogens and carbon-monoxide which is a known killer. Think of the rotten-egg smell as an early-warning system that there's exhaust gas in the air around you. Excessive gas can also be a symptom of a car's engine that is not turned correctly.

It's really important not to run a car engine inside a garage for any longer than is absolutely necessary as these toxins can build up very quickly. It sounds like your garage is attached to your house, and that reminds me why garages were once separate to the house they served. (As were kitchens in the very old days, as a means of ensuring a kitchen-fire didn't take the rest of the house with it.) Don't be tempted to reverse into the garage, instead drive in nose-first, leaving the tailpipe nearest the garage opening and never start the car with the garage door closed.

It won’t fit without a lot of engineering. If you seriously want to do it you will need to talk to a qualified engineer recognised by Vicroads, and have a large amount of money at your disposal.

I would use the factory recommended oil, at least while the car is under warranty. Once the warranty has expired you could use the Mobil oil and shouldn’t experience any problems.

All of the cars you name meet your criteria of size, economy, performance and handling.

You could also add the Mazda3 and 6 to the list.

Of all of those I would nominate the Camry as the great all-rounder.

The Impreza is approved to run on 91-octane, so there should not be any issues caused by the fuel.

We checked with Subaru and were told that you should follow the manufacturer's recommendation for engine oil as specified in the owner's manual. Subaru also told us that 0W-20 engine oil is available in Australia and can be purchased through Subaru dealers. They also said that you could rest assured that although the engine will not be delivering maximum power, maximum torque, best fuel economy or best exhaust emissions, no harm will have come to the engine by using 10W-40 engine oil.
 

Subaru says the belt should be changed every 100,000 km or four years, whichever comes first. If it hasn't been changed since new then it should be changed as soon as possible.

WE CONTACTED Subaru with your question and asked for their response, which was: ``We recommend the use of fuel additive SA718 every 6000km to prevent flaking of carbon in the combustion chamber that can be caused by additives in some brands of petrol. Typically what happens is after a short run, usually just moving the car on a Sunday afternoon to wash it, the additive in the fuel soaks on the carbon deposit in the combustion chamber and causes it to flake off. Because of the characteristic of a boxer engine with its cylinders lying on their side, the flaking carbon falls onto the seat of the open exhaust valve. When the engine is cranked to start the carbon particle prevents the closing of the exhaust valve. This means no engine compression and therefore the engine doesn't start. The spark plug is soaked in fuel and this also prevents starting even if the carbon particle becomes dislodged during the cranking. If the engine starts it often runs roughly for a while as the excess fuel is burnt off. The additive that we recommend, SA718, acts to counter the additive in the fuel and stops the carbon from flaking.''

THE short answer is yes, but it might not be all that easy. There is no technical reason why it can't be done successfully, but you need to find an approved kit with emission compliance and an installer experienced in doing the conversion. I would talk to WRX specialists and get their opinion.

THANKS for the advice. It's certainly worth checking.