to increase mpg what is the normal engine warm up time ?

[rich83]

True... But I fail to see how waiting X minutes before moving has any benefit on the car.

[scottm72]

^^^^
Oh dear! Does this mean I have been doing it all wrong for 104,000 miles?

That clunk of the DSG reverse is not an encouraging sound. And what about that very experienced Ferrari driver I used to know who always spent time warming up the engine?

Why is it different for a F1 racing engine? They are always warmed up before engaging gear?

Isn't this why the 2.0T FSI engine starts off at ~1000 rpm and doesn't drop revs for the first moments or two?

rr has a fair point here, logic would dictate that putting any kind of engine under stress straight away is not a good thing but saying that i can understand the other point of view.
im still thinking more along the lines with red robin here but if anyone knows any better then please post it

[rich83]

Well for a start.. a road car doesn't idle at ~10,000RPM, and rev to 18,000RPM. If I remember correctly... F1 engines are built to such a high tolerance that they are effectively seized when cold.

[scopes]

Well it takes a min for the automatic choke to stop, i would have asumed that driving straight after that would have been safe and always have done...

As far as im aware, the oil needs a chance to get up round everything that needs to lubed...

[Squeeguk]

^^^^

Why is it different for a F1 racing engine? They are always warmed up before engaging gear?

An F1 engine, and almost all very high performance race engines are pre-heated before starting them by pumping pre-heated fluids into them for a period of time before starting them. The engine is literally at operating temperature when it's started. The 'warm up' procedure of an F1 engine is to ensure all systems are fully functional and operating correctly before heading out. In F1 cars, they even do this to the gearboxes.

As previously mentioned, these engines are literally seized when cold due to the tolerances.

I've had one of my previous cars clock up over 300k kms driving from startup with no problems at all and just regular servicing.

Keep in mind, most people have to reverse out of a driveway before heading off. This is more than enough 'idle' time before driving off.

During Winter, my next door neighbour comes out, starts his engine, then goes back inside to have his cuppa before getting in the car after around 15 to 20 minutes of idling. Best way to reduce the life of an engine.

[RedRobin]

^^^^
Point taken about the F1 engines - As richwig has said: They are different.

I only wait for the engine revs to drop and settle as they do automatically after usually less than one minute and without any help from me. I don't go off for a cuppa etc.

As said, if I engage gear on the DSG before the revs have dropped, the DSG does a hard clunk. Whereas once the revs have dropped, the shift is smooth.

The revs at startup suggest the use of an automatic choke and that will be part of what VW have designed to happen - For a reason.

[dan930]

I also fire the car up & let the revs drop (around 1-2mins) then drive off..

[scottm72]

^^^^

Why is it different for a F1 racing engine? They are always warmed up before engaging gear?

An F1 engine, and almost all very high performance race engines are pre-heated before starting them by pumping pre-heated fluids into them for a period of time before starting them. The engine is literally at operating temperature when it's started. The 'warm up' procedure of an F1 engine is to ensure all systems are fully functional and operating correctly before heading out. In F1 cars, they even do this to the gearboxes.

As previously mentioned, these engines are literally seized when cold due to the tolerances.

I've had one of my previous cars clock up over 300k kms driving from startup with no problems at all and just regular servicing.

Keep in mind, most people have to reverse out of a driveway before heading off. This is more than enough 'idle' time before driving off.

During Winter, my next door neighbour comes out, starts his engine, then goes back inside to have his cuppa before getting in the car after around 15 to 20 minutes of idling. Best way to reduce the life of an engine.

nice to get the ice of the car i guess but wouldnt someone just steal it when it is sitting there running 

[Squeeguk]

^^^^

Why is it different for a F1 racing engine? They are always warmed up before engaging gear?

An F1 engine, and almost all very high performance race engines are pre-heated before starting them by pumping pre-heated fluids into them for a period of time before starting them. The engine is literally at operating temperature when it's started. The 'warm up' procedure of an F1 engine is to ensure all systems are fully functional and operating correctly before heading out. In F1 cars, they even do this to the gearboxes.

As previously mentioned, these engines are literally seized when cold due to the tolerances.

I've had one of my previous cars clock up over 300k kms driving from startup with no problems at all and just regular servicing.

Keep in mind, most people have to reverse out of a driveway before heading off. This is more than enough 'idle' time before driving off.

During Winter, my next door neighbour comes out, starts his engine, then goes back inside to have his cuppa before getting in the car after around 15 to 20 minutes of idling. Best way to reduce the life of an engine.

nice to get the ice of the car i guess but wouldnt someone just steal it when it is sitting there running 

Nah, we live in a cul de sac in a private gated estate, so its fine.

[itismebigd]

Imo and it is only my opinion,id go for the set off straight away keeping the revs to a minimum while waiting for the temp to level,im probably on the same page as RR in the respect that i probably love my car way to much,in that i dont want to do anything to compramise the awesome performance of the gti especially as i am now running the k04 upgrade,im probably way to sympathetic to it in regards as the wife says "its only a car" lol but im engineering wise to the effects of driving it sorely if that makes sence lmao

Dougie

[RedRobin]

During Winter, my next door neighbour comes out, starts his engine, then goes back inside to have his cuppa before getting in the car after around 15 to 20 minutes of idling. Best way to reduce the life of an engine.

nice to get the ice of the car i guess but wouldnt someone just steal it when it is sitting there running  

....Yes, potentially someone could steal it and there have been many cases of opportunists stealing cars while their owners go back indoors leaving the engine running to defrost/de-ice the glass in winter. AFAIK, the insurance companies deem this as negligence and don't pay out.

[itismebigd]

100% right Robin,the insurance company will not pay out if you leave your keys in the ignition or the car running,one of my m8`s did this very thing at a petrol station left the keys in it and the above happend the car got stolen insurance refused to pay out,due to the fact that the car was not properly secured.

Dougie

[RedRobin]

.
What drops out of this discussion when starting up from cold, is that:

- It's not okay to leave the engine idling for a long time after the revs have settled automatically.

- It's not okay to highly rev the engine before a mile or two has been gently driven to get operating temperatures up to normal.

- It's okay to let the engine automatically settle its revs (usually approx a minute) before engaging gear.

- There is no hard evidence of harm being done to the engine by engaging gear before the revs settle except that doing so clunks a DSG and that is better avoided.

- How all this influences mpg is questionable whether it does so at all.

Conclusion is that many of us do indeed love our cars too much (as alleged by wifeys, girlfriends, and partners) and that we would all love to have this startup music to start our day:

^ Proof that a car is much more than just a machine - It lives and breathes!

[gazon69]

It actually states in the handbook that when starting the vehicle, drive off straight away but do not rev the car above 4k rpm, i think it was, untill OIL is up to temp. Dont go off of the temp gauge in the car as that is water temp.

[RedRobin]

It actually states in the handbook that when starting the vehicle, drive off straight away but do not rev the car above 4k rpm, i think it was, untill OIL is up to temp. Dont go off of the temp gauge in the car as that is water temp.

....I've always said that VW are wrong not to have included an oil temp gauge on the GTI. I think the GT has one.

I don't like the DSG clunk if I engage gear before the revs settle, so I'm going to continue as I have done and drive off after the revs have automatically settled, which only takes a minute.