Allways sad to hear a fathers passing, his car and service habits speak well of him... How fortunate you are to keep his memory so alive by tacking over care of his much loved car... Toyota is so advanced, there is not much to do to keep it in good order... power should be quite strong. Importantly, oil and filter were in good hands, change every 10K klm or less, say 12mnths.. Air filter is important, & very easy for u to change... get a genuine unit. Spark plugs probably don't 'need' changing... but why not freshen them up with newies... post a how to 4 good advise. Fuel filters... Again post for advice... I never changed on your model :) If these couple easy things don't help, post again, now they have been done we can move to having your O2 sensor checked, cheap and easy... it may be sluggish. And have your 'codes' read at the same time... will indicate some existing prob, not immediatly obvious. Both the above checks can be got for free by mechanics with the equipment, just by asking them. Nulon is a good internal component protection and anti friction measure and the different fuels will not make much diff to performance... but cars do need plenty of air, and good spark, and good engine management... After that we're looking at 'draging' disc pads, half flat tyres, or a boot full of bricks, ( unlikely) but weight is not wanted. Do what you can yourself, we will help you, learn your dads car... it's all pretty easy. Let us know how you go... cheers. Others that know more than me should chime in with advice... it's a good project. Grab a K&N high flow air filter for it they are a bit exy but it'll be the only one you will ever need to buy for that car as they are non disposable. Best thing to do for any car is clean out the intake to gain econemy and power. After that just normal service with good quality parts and product and the car should well last you for years to come. Also highoctane petrol will help to make the car have a bit more kick to it and aslo better econemy in my experience however the change will take a little while as the ecu has to adjust itself to do this. Hope this helps Just did an oil & filter change myself, used Nulon Oil Flush first, then Castrol GTX3 oil. Added a Nulon oil treatment, Nulon Octane Boost and a K&N air filter. It has had a dramatic effect on performance and smoothness. Many thanks for the advice on the K&N, well worth the extra money. Will only be using premium unleaded from now on. The mechanic my father used had put some sort of gel on the sump plug to protect it. It was easy to peel off with a screwdriver and has left the plug in pristine condition. I went to an AutoPro shop to see if they had something similar and they said it was the first time they had heard of someone doing that to a sump plug. I think it is a great idea but am not sure what the mechanic used (he has since retired). Any ideas?