1994 Toyota Camry Pricing and Specs

There’s no reason to think the Hybrid will not last as long as a regular petrol vehicle.

Toyota has been making hybrids for many, many years and they have never shown any sign of being less durable or reliable then the company’s petrol models. The batteries are said to last the lifetime of the vehicle, so there’s reason to be concerned about that either. The thing with the hybrid is the higher purchase price. That’s offset by the lower fuel consumption, so the longer you keep the vehicles the greater the chance to recoup the extra initial cost.

The other thing to consider is that hybrids work at their best in stop-start city traffic, they are not so good out on country roads where the petrol engine comes into play more of the time.

The CVT oil should be changed every 100,000km. As for the fuel consumption it's best to do a check yourself by measuring how much fuel it is actually using. Judging the consumption by how far the gauge falls is very inaccurate, and I wouldn't stake my life on the fuel consumption gauges in the car. Do an actual measurement and you will know exactly what the consumption is. Nissan claims an average of 9.1L/100km, 7.7L/100km on country driving, and 11.5L/100km on city use. I would expect your car would fall somewhere between 9.1 and 11.5L/100km.

I'd say you have an engine problem, perhaps a cracked head.  Chemiweld is mostly used for a temporary repair to seal a crack in the cooling system without tearing the engine down and doing a proper fix. It's worked to some degree in that the engine is no longer running roughly and there is less steam coming from the exhaust, but the problem still appears to be there. Pull the engine down and find the real cause of the problem.