Toyota Corolla Engine Problems

No matter which brand of fuel you use, you shouldn't be getting a pungent smell through the air vents. It sounds to me like there's a problem with a seal not doing its job in the engine bay, or around the plenum chamber.

I don't know what he's trying to tell you, but it sounds like the "rubbish" is coming from his mouth. But I would continue to have it serviced every six months as you have been doing, that should be more than sufficient to keep it in tip-top shape.

Any of those oils would be perfectly ok for your car. If you are doing really short trips and want the engine to warm up a little faster, and reduce wear during that period, you could use a 10W-40 oil, but I would use a 20W-50 oil as a good all-rounder.

Regular 91-octane unleaded petrol.

Yes, you won't have caused any damage, the starter won't have engaged.
 

The process is the same as any other car. Look up what grade of oil your car needs and how much oil capacity it has, all of which is listed in your owner's manual, and purchase a brand new oil filter. Drive the car for approximately 10 minutes to ensure the oil is warm as this makes it easier to drain. Park the car on a level surface, open the bonnet and loosen the oil filler cap so it is just resting on top of the filler tube, then slide a drain tray underneath your engine. There will be a small flap in the undertray to be undone so you can access the 14mm oil drain plug with a ring spanner. Undo the sump plug being careful not to burn yourself as the hot oil rushes out. Let it drain for 10minutes, then do up the sump plug with a new washer and being careful not to over-tighten the plug - do it snug, then turn it another quarter-turn. Slide the drain pan under the oil filter and remove this again being cautious to not splash hot oil on yourself. Before installing the new oil filter check the rubber seal came off with the old filter, then smear a little fresh oil on the new filter's rubber seal before winding it on and doing it up a quarter-turn past snug. Fill the engine with fresh oil as per the owner's manual. Once you have confirmed there is no oil leaking out, start the engine, let it warm up and then check the oil level. If you cannot reach under your car to undo the oil filter or sump drain plug, use the factory jacking points recommended in the owner's manual to lift the car off the ground at the front and rear, lifting the front first, and use four weight-rated chassis stands to support the car at the factory recommended support points.

The only way to resolve a problem is to report it, first to the dealer, then to the carmaker if that doesn't solve it. After that it becomes difficult. My view is that there should be an industry ombudsman who can resolve issues between carmakers and their customers.
 

The coolant change period does seem too long, the initial change is at eight years, which would seem way too long. I would be looking to change the coolant every couple of years, that's 40,000 to 50,000 km. As for the automatic transmission, carmakers now employ a fill-for-life strategy, which means they fill the trannie in production and never touch it again. My view is that it's a flawed approach, particularly if you plan to keep your car for a long time, as you say you are. I would have the fluid changed every 50,000 km and have the transmission serviced every 100,000 km.

No, it isn't normal. You should take your car to the dealer and have them investigate it. Leave it with them overnight if necessary and even be with them when they start it, so you can point out to them the noise that you are concerned about.

Years ago when you owned your Torana it was considered something of a performance car, as the Clubsport, SSV and Calais are today, but there are many other ways of getting your driving thrills today without having to go for a V8. Some of the hot hatches now available would give you all the thrills, and more, than the big-bangers of old. Take a test drive in a VW Golf GTi or one of the fast Ford Focuses and I'm sure you'd rethink your choice. All the cars you mention, the Clubsport, SSV and Calais are good cars with plenty of grunt, the V8 sound, and the comfort of a big car. For mine though I'd be going for a hot hatch.