Nissan Maxima Engine Problems

The engine warning light was telling you that there is a problem within the engine management system. Going into 'safe', better known as limp home mode, is a fail-safe system that allows you to drive the car, albeit at a much reduced pace, until you can get to a mechanic to have it fixed. The error codes that have been found should assist the mechanics to find the cause of the problem and fix it. There is really no choice, but to press on with the mechanics and trust them to find and fix the cause of the problem. If you doubt their competence then take your car somewhere else. Today's cars are much more complex than cars in the past, and most problems seem to affect the computer systems that effectively control them. They're much harder to fix than the cars of old.

The engine is tuned to run at its peak on Premium Unleaded fuel, which has an octane rating of 95. By using that fuel you will get better performance and better fuel economy, most likely better fuel economy than you would when running on the cheaper Regular unleaded. Nissan approve the use of E10 ethanol blend fuel, so that would be the best alternative fuel if you can't afford Premium.

If the knock sensor was at fault it would show up as such on a computer check, and changing the plugs to colder ones is unlikely to do anything, and it's not possible to reset the ignition. Check the airflow meter and have a carbon clean carried out. The most likely cause of the problem is a build-up of carbon in the engine.

First, you need to put Nissan's attitude to running its cars on LPG into context. Nissan doesn't design or test its cars on LPG, so it has no knowledge of the impact of doing so. If they supported changing to LPG Nissan would, in effect, be taking on the responsibility for what might happen should you convert to LPG, so they advise against it. It's actually got little to do with whether or not their cars would happily run on LPG or not. The problem you will have is finding a certified kit for the conversion. Because of the low demand for converting the Maxima kits haven't been developed.

Nissan’s recommendation is to use 95-octane fuel, and it says it is suitable to run on E10.

It seems to be temperature related, and sounds like an engine sensor is playing up, it could be a connection that's faulty. Have a mechanic, preferably a Nissan specialist check the sensors and their connections.

Independent Nissan service specialist Jerry Newman suggests you check the idle control valve and the air mass sensor, the latter doesn’t always show up as a fault on a diagnostic check.

Nissan specialist Jerry Newman tells us that 20w-50w is regarded as a little heavy for a modern multi-valve engine, and that 10w-40w or 15w-40w is preferable depending on the temperature of the area you live in. Either grade would be suitable for your area, but the 10w-40w would be better if you were driving regularly to the snow where it would be much colder.

I would have suggested that you clean the injectors, but as you have already done that I would go through the plugs, leads, coils etc. and make sure all is well with them, and make sure the idle is correct.

MOST modern engines use belts, but not all of them. Timing belts are used because they are cheaper than chains and also quieter. Nissan has used chains on passenger car engines since the 1980s and commercial engines since 2000.