Diesel vs petrol

ice_cubes

ice_cubes

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...Does it really matter if you are going to use the car for going to & from work?
 
Diesel more expensive to buy, higher maintenance cost but cheaper fuel costs, more torque
Petrol cheaper to buy, lower maintenance costs but more expensive fuel costs, more power

For start-stop city traffic a diesel auto is a winner
 
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ice_cubes said:
...Does it really matter if you are going to use the car for going to & from work?
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End of the day, the savings you get from Diesel goes into maintenance. The running cost on diesel like for like should be slightly higher than Petrol. It's about driving style and what you need to get out of it. If you want low rev high torque then go diesel. If you want a smoother acceleration and easier maintenance then go Petrol.

Diesel engines though, if treated correctly can last a thousand years due to the low revs. Petrol engines don't last that long due to the speeds at which the engine operates.
 
ice_cubes said:
...Does it really matter if you are going to use the car for going to & from work?
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Probably preference - but,

Diesel - generally speaking - are lower revving engines, have better low end torque, use less fuel and as oil burners wear and tear better ....

I drive a diesel to work and wouldnt want a petrol again. Personal choice I spose.
 
awesome :)
Got myself the A180 CDI . Will see how it goes as time passes
 
Rough rule of thumb:

1. Naturally aspirated petrol engine loses about 18-20% power in Gauteng compared to at sea level, for example a 1.6l in Gauteng will perform about the same as a 1.3l at the coast. Turbo's usually offset this loss. Therefore a turbo-diesel has access to all of its available power/torque. Same with turbo-petrol engines.

2. Diesel has about 30% better fuel economy. This will be less compared to some of the newer generation petrol engines.

This is a rule of thumb and NOT absolute. Your driving style will determine actual fuel economy figures.

3 years ago I upgraded my 1996 Fiat Uno Fire (1100) to a 2011 Nissan Micra 1.5 dCi. I have found my driving style well suited to diesels. I value efficiency over raw power. The fact that the Micra can't really go over 140 km/h does not bother me at all. It has lots of torque for such a small engine. And I use my car almost exclusively as a commuter from Joburg to Centurion each day.
 
ice_cubes said:
...Does it really matter if you are going to use the car for going to & from work?
Click to expand...
I use my i20 Diesel to and from work mostly and it has saved me a tank of fuel per month over the last year year.
That's +- 600*12.

There is no major difference in prices for Maintenance\Service plans between diesel and petrol these days.
Older diesel cars got serviced more regularly and had much more maintenance.

Times have changed :) diesel cars now get serviced between 15000-20000km with every second service being only the normal old and filter change.
 
I checked some of the old posts (2009/2010) & I see they mention something about letting the diesel car idle for a few minutes before turning the ignition off. Is this still relevant in 2015?
 
ice_cubes said:
I checked some of the old posts (2009/2010) & I see they mention something about letting the diesel car idle for a few minutes before turning the ignition off. Is this still relevant in 2015?
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The reason for idling before switching off is to let the turbo cool off. During operation, especially when driving on the highway, the turbo spins up and reaches incredible rpm's. This generates a lot of heat and the turbo will become red-hot.

While the engine is running, oil/cooling fluids are pumped through the turbo. This means that the temperature is kept under control.
The moment you switch off the engine, no more oil is pumped through the turbo. This means the heat is not carried away. The heat is now dumped into the air and into any surface in contact with the turbo, usually bushes/bearings. These surfaces aren't meant to handle that much heat. An Audi mechanic friend of mine told me that most turbo failures he saw was due to the bushes "burning through". Alternatively the turbo will just disintegrate.

It is possible to install a "turbo protector" on some diesel engines. This device keeps the oil pumping through the turbo even after the ignition has been switched off. Some, not all, modern diesel cars come with a similar system pre-installed.

Usually when driving around town at 60km/h, chances are the turbo won't get that hot and will have cooled down by the time you want to switch off.

For myself, I always wait 30-60s before switching off. That is time well spent when compared to the cost of replacing a turbo.
 
ice_cubes said:
I was told its the Micra 1.5dci - not sure if its still true
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As far as I know Nissan no longer makes/sells the Micra 1.5l dCi. It really is a pity since this is a very nice city car.

Reliable, cheap to run and not that expensive to maintain. Mine is going in for its 75 000 km service next week.
 
I have done the sums in a thread somewhere, a diesel vehicle can easily cost R20 000 or more to buy the same specification model than the petrol. And then it depends how far you drive per year on how soon you start saving due to the better fuel efficiency. It can easily be 5 or more years before you start saving money (and that's just when factoring the initial higher purchase price) if do the usual 15 000 to 20 000km a year...

So in conclusion, go petrol if your wallet matters.
 
PsYTraNc3 said:
I use my i20 Diesel to and from work mostly and it has saved me a tank of fuel per month over the last year year.
That's +- 600*12.

There is no major difference in prices for Maintenance\Service plans between diesel and petrol these days.
Older diesel cars got serviced more regularly and had much more maintenance.

Times have changed :) diesel cars now get serviced between 15000-20000km with every second service being only the normal old and filter change.
Click to expand...

Till something goes wrong.

On a Petrol engine a repair is cheap and mechanics are plenty. If a Diesel engine breaks. Get ready to apply for a personal loan :D
 
Also forgot to state, my post is if buying a diesel vehicle new, second hand if one does not pay more for the diesel than the equivalent petrol, then you will start saving immediately.
 
Pitbull said:
Till something goes wrong.

On a Petrol engine a repair is cheap and mechanics are plenty. If a Diesel engine breaks. Get ready to apply for a personal loan :D
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You tell us this now AFTER I bought the diesel .... :)

No, seriously my diesel Tucson - 6 years, no issues - Santa Fe now 6 years old ... also no problems - ...... yet.
 
AntennaMan said:
The reason for idling before switching off is to let the turbo cool off. During operation, especially when driving on the highway, the turbo spins up and reaches incredible rpm's. This generates a lot of heat and the turbo will become red-hot.

While the engine is running, oil/cooling fluids are pumped through the turbo. This means that the temperature is kept under control.
The moment you switch off the engine, no more oil is pumped through the turbo. This means the heat is not carried away. The heat is now dumped into the air and into any surface in contact with the turbo, usually bushes/bearings. These surfaces aren't meant to handle that much heat. An Audi mechanic friend of mine told me that most turbo failures he saw was due to the bushes "burning through". Alternatively the turbo will just disintegrate.

It is possible to install a "turbo protector" on some diesel engines. This device keeps the oil pumping through the turbo even after the ignition has been switched off. Some, not all, modern diesel cars come with a similar system pre-installed.

Usually when driving around town at 60km/h, chances are the turbo won't get that hot and will have cooled down by the time you want to switch off.

For myself, I always wait 30-60s before switching off. That is time well spent when compared to the cost of replacing a turbo.
Click to expand...


Ok, makes sense. I will keep that in mind

supersunbird said:
Also forgot to state, my post is if buying a diesel vehicle new, second hand if one does not pay more for the diesel than the equivalent petrol, then you will start saving immediately.
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Awesome :) I bought it second hand :)
 
TEXTILE GUY said:
You tell us this now AFTER I bought the diesel .... :)

No, seriously my diesel Tucson - 6 years, no issues - Santa Fe now 6 years old ... also no problems - ...... yet.
Click to expand...

Yea, they are awesome engines if you look after them. But seriously get a quote on a Diesel engine if it was to break. Injectors alone I think runs at R 2k EACH That's R8k just for injectors. /faint
 
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