Nissan Pulsar Engine Problems

It could be due to bad fuel. Run it out as best you can, or drain the tank, and refill with fresh fuel from another servo, preferably one that sells a lot of fuel so you can be confident the fuel is fresh.

If it still does it then look for other causes, such as fuel filter, fuel pump, air filter, throttle body, spark plugs.

The first thing to do is to give it a tune-up, with new spark plugs, replace the air cleaner, and clean the throttle body.

It’s unlikely to be electrical, or the gauge itself. It’s more likely to be the thermostat, but before you do anything make sure the cooling system is filled to the full mark.

Try adding some fuel system cleaner to the fuel the next two or three times you refuel. If that doesn't help, have the throttle body cleaned.

If it's a manual it could be that she's trying to drive it in too high a gear and she should change down to a lower one. If it's automatic I would be looking at the engine idle settings to make sure that they are correct and the engine is not idle is not set too low. Changing fuel makes no sense at all.

If the Pulsar is in good condition, as you seem to indicate, it might be best to repair it. A mechanic should be able to work out if it's a head gasket problem or a cracked head and from that give you a cost to repair the engine. It might be better to spend a few hundred dollars on repairs than spending a similar amount on another old car that might itself have problems. Trade-ins are generally passed down the line, from dealers to used car lots, until they are no longer viable and they are then scrapped. Check local used car yards. If they don't have a car for you give them an idea of what you want and they might be able to source one. There are also plenty of websites offering used cars for sale, and they are probably the best place to start shopping. If you need help using the sites, get a friend or relative to help. 

It's most unusual for an engine to break a connecting rod under normal driving conditions if the engine has been serviced regularly and the oil changed. After so many years it's unlikely to be a manufacturing fault, so I doubt that you would have any chance of getting Nissan to even listen to your case. I would suggest you take up one of the offers you have in front of you.

If there is a sudden loss of power, as you describe, I would be looking for an electrical fault, perhaps a faulty sensor, such as the crank angle sensor.

It could be a sensor that’s playing up and sending the wrong signal to the computer on occasions, a sensor like the crank angle sensor, or it could be as simple as the fuel injectors needing a clean.

Nissan says only models post 2004 can run E10, which isn’t a lot of help for owners of older models like yours. The 1999 Pulsar hatch has multi-point fuel injection, so there’s little chance of you having a problem with E10. If you were concerned about the effects of E10 you could run premium unleaded.