[Gazi]

This will be my first diesel engine... so Im interested in knowing more about these engines compared to petrol.

So far I have read they...

Takes longer to warm up therefore bad for short trips. Is it worth letting the car warm up first before setting off?

Are more suited to load? (what does this mean in terms of driving style and engine break-in?)

Any other information would be great...Thanks!

[G33]

they make a horrible racket

[briers]

Congrats on your new purchase

Many just drive their cars normally from the word go. I prefer to do a mini run in.

Essentially, gradually increase the revs up to 1,000 miles. E.g stay under 3k rpm for the first 300 miles. Always use varying degrees of throttle but avoid max acceleration and labouring the car. Try not to use cruise control. Vary the revs and do not baby the car.

Always let it warm up before giving it any stick and don't idle it to warm it up.

Give it plenty of load, i.e. occasionally accelerate quick heavily between 1.6 and 2.5k rpm. Maintain a steady speed at around 1.3k - 1.6k.

You can cycle them giving them plenty of beans between 1.6 and 2.5k, then slow down again and repeat. Find a hill, do the same up hill for max loading. Then run it at 2.5k at a light throttle, then drive normally.

The idea is to never baby it, avoid red lining, always let it warm up, vary the acceleration force and vary the revs, favouring more stronger performance.

After about 300 miles venture over 3k and by 1k miles you should be hitting red line occasionally.

I'm fairly sure the 320d turbo should be water cooled after shut down but let it idle for 10 or 15 seconds before switching off and make sure you stay under 1.7k for the last 1 or 2 miles before your destination.

[AlwynMike]

Originally Posted by briers

Congrats on your new purchase

Many just drive their cars normally from the word go. I prefer to do a mini run in.

Essentially, gradually increase the revs up to 1,000 miles. E.g stay under 3k rpm for the first 300 miles. Always use varying degrees of throttle but avoid max acceleration and labouring the car. Try not to use cruise control. Vary the revs and do not baby the car.

Always let it warm up before giving it any stick and don't idle it to warm it up.

Give it plenty of load, i.e. occasionally accelerate quick heavily between 1.6 and 2.5k rpm. Maintain a steady speed at around 1.3k - 1.6k.

You can cycle them giving them plenty of beans between 1.6 and 2.5k, then slow down again and repeat. Find a hill, do the same up hill for max loading. Then run it at 2.5k at a light throttle, then drive normally.

The idea is to never baby it, avoid red lining, always let it warm up, vary the acceleration force and vary the revs, favouring more stronger performance.

After about 300 miles venture over 3k and by 1k miles you should be hitting red line occasionally.

I'm fairly sure the 320d turbo should be water cooled after shut down but let it idle for 10 or 15 seconds before switching off and make sure you stay under 1.7k for the last 1 or 2 miles before your destination.

This man speaks a lot of sense!!

Back in the heady days of the 70's, my father bought a new car. At the same time, one of his clients bought an identical car (or as identical as a British Leyland could be!). My Old Man's car was run in nicely, as above, the other car was driven pretty hard from the word go. The other car, some 3 years later, with both cars having a similar mileage, was noticeably quicker than the Old Man's. The downside is that the Old Man's car was still running sweetly after 10 years, whereas the other had been long scrapped!!

Mike

[Gazi]

Originally Posted by briers

Congrats on your new purchase

Many just drive their cars normally from the word go. I prefer to do a mini run in.

Essentially, gradually increase the revs up to 1,000 miles. E.g stay under 3k rpm for the first 300 miles. Always use varying degrees of throttle but avoid max acceleration and labouring the car. Try not to use cruise control. Vary the revs and do not baby the car.

Always let it warm up before giving it any stick and don't idle it to warm it up.

Give it plenty of load, i.e. occasionally accelerate quick heavily between 1.6 and 2.5k rpm. Maintain a steady speed at around 1.3k - 1.6k.

You can cycle them giving them plenty of beans between 1.6 and 2.5k, then slow down again and repeat. Find a hill, do the same up hill for max loading. Then run it at 2.5k at a light throttle, then drive normally.

The idea is to never baby it, avoid red lining, always let it warm up, vary the acceleration force and vary the revs, favouring more stronger performance.

After about 300 miles venture over 3k and by 1k miles you should be hitting red line occasionally.

I'm fairly sure the 320d turbo should be water cooled after shut down but let it idle for 10 or 15 seconds before switching off and make sure you stay under 1.7k for the last 1 or 2 miles before your destination.

Thanks for the advice... how can I incorporate this with the auto box? I assume do everything in D until I pass the 1k miles?

[kaishang]

I wonder if it does anything to keep revs low in the last mile of driving, provided the engine is at idle prior to turning it off.

The turbo will spin in proportion to the speed of the exhaust gas going through it. While the engine is running, the turbo is also doing work compressing the intake air so that it can't remain spinning fast without high exhaust gas flow from the high engine rpm to maintain high turbo rpm, ie the turbo rpm should follow engine rpm with minimal delay.

Or am I missing something?

[HighlandPete]

Originally Posted by Gazi

This will be my first diesel engine... so Im interested in knowing more about these engines compared to petrol.

Takes longer to warm up therefore bad for short trips. Is it worth letting the car warm up first before setting off?

Are more suited to load? (what does this mean in terms of driving style and engine break-in?)

Any other information would be great...Thanks!

I've had a lot of experience with diesel's over the years, well before the modern 'fashion' to have a diesel car.

As diesel engines are thermally more efficient than petrol, they do take longer to warm up. Don't try and warm them up on ldle, drive off after a few seconds, allow time to for the oil to get around (be kind to the turbo) and don't rev them hard from the off. I know most comment is about cooling turbos, before you switch off, (more to do with petrol turbo temperatures than the cooler diesel exhaust gases), but most don't realise more wear occurs due to less care on warm up. Don't rev the engine hard when cold, even off load. Think more of the turbo when you start up, than when you switch off. Still good practice to allow a little cool off from a hard drive. Don't just pull off the motorway, after a hard haul and and switch straight off, give it a few extra seconds on idle, before shut down.

A diesel engine works best at a steady load, doesn't have to be hard, but it won't hurt it, unless it's overfuelling (soot levels) but achieves the best fuel consumption at a light load when there is little turbo boost. Using high revs on WOT can be pretty thirsty for a diesel, the fuel efficiency drops off quite fast. Riding the torque is what driving a diesel is really all about.

Diesel's don't do well on short trips, with cold starts, particularly in our often wet/humid winter climate, loads of extra gunk and goo can build up. I run a 3.0 litre diesel, but often think, when I need to do a few short trips, it is not the best for it. It's the key reason I run a premium fuel, to try and help keep it a bit cleaner inside. I often think getting back to petrol would be better for any engine I use, for local work.

I know a lot choose a diesel engine for tax and perceived mpg savings, but often the diesel engine isn't the best choice. As we are now getting more mileage from users converting to diesel, the issues are throwing up. EGR failures, DPF failures, gunked up manifolds and valves. Even 'decokes' to get the muck out. Not the engine choice for heavy urban driving, or grandma doing the local weekly shop. Motorway mileage munchers, ideal.

HighlandPete

[HighlandPete]

Originally Posted by kaishang

I wonder if it does anything to keep revs low in the last mile of driving, provided the engine is at idle prior to turning it off.

The turbo will spin in proportion to the speed of the exhaust gas going through it. While the engine is running, the turbo is also doing work compressing the intake air so that it can't remain spinning fast without high exhaust gas flow from the high engine rpm to maintain high turbo rpm, ie the turbo rpm should follow engine rpm with minimal delay.

Or am I missing something?

It is not really the speed of the turbo spooling, although often that is what is focused on. It is the heat in the turbine that's our issue, and we are trying to reduce the temperature 'a little' by light load. Our latest oils don't coke in the same way older blends did, so even the potential 'cooking' of the oil on the shaft, bearings and seals is not so critical as it once was. But no harm taking a bit of extra care on shut down, to help longevity.

HighlandPete

[Jeff123]

The thing with a diesel is that people (including me) look at the expected performance figures and the mpg; and it seems a no-brainer. Mine is only a 2 litre (177) but it does 143mph, 0-60 in c8.0 seconds and is supposed to acheive an average of 52mpg. That's sports car performance for supermini economy. The truth is different, but that's what attracts people.

[Carjack]

I went from auto 320i to a 320D purely for its better acceleration and fuel economy, 50+ mpg is no prob on the motorway. I just do not use it just for shopping trips and the like. (well I try!)

[Gazi]

About varying the throttle during break in....

When can I start using the cruise control?

[Jules6]

I am convinced that BMW programme in some protection. Don't ask me how.
My car didn't feel that hot from new but when it clocked 1000 miles almost to the mile it was like a switch and was noticably livelier.
Well that's my conspiracy theory anyway

[dxb335d]

Don't even waste 1 mile running in your car. It will ave 5-10 miles on it and seen the redline already. Not to mention being run on a set of rollers.

Good luck with the purchase.

[dxb335d]

Originally Posted by Jules6

I am convinced that BMW programme in some protection. Don't ask me how.
My car didn't feel that hot from new but when it clocked 1000 miles almost to the mile it was like a switch and was noticably livelier.
Well that's my conspiracy theory anyway

Mine was tight at first but not in anyway controlled or had any protection. That's all in your head.

[Tipper]

I've found that a diesel engine (any make) does not really perform until past 30-40k miles. After that it will fly!

Not sure when the performance tails off though...