[MihirC]

Originally Posted by swissknife

From a cold start @ 30 deg C, it took about 10 minutes 15 seconds, idling, to get to 90 deg C (the max that it reaches) on my GT TSI with the A/C turned off.

On normal driving, it takes about 1.5 Kms / 5 mins with normal city traffic with the A/C turned off.

Note: I do not turn on my A/C till the engine temperature reaches its max (90 deg C).

Does it affect or is detrimental to the engine if we put the AC on before the temperature reaches 90 degrees?

[swissknife]

Originally Posted by MihirC

Does it affect or is detrimental to the engine if we put the AC on before the temperature reaches 90 degrees?

The A/C compressor does load the engine and it is not preferred to load the engine when it has not reached its optimum running temperature. Lubricating fluids need to be at a certain temperature range for them to be effective. Over loading the engine when the lubricating fluids are not at their optimum temperature could lead to reduced life span of the engine components.

[asitkde]

Originally Posted by MihirC

Does it affect or is detrimental to the engine if we put the AC on before the temperature reaches 90 degrees?

I don't think, it is harmful to put the A/C on before the engine temperature reaches 90 degrees. The booklet says nothing of that sort. But, one should not push the engine hard before it reaches 90 degrees, with or without A/C.

I can tell you what I follow as a routine.

When I turn the engine on for the first time in the day, for the initial few seconds (something like 20 - 30 seconds) the idling is noisy and at 1200 rpm or so. I never turn the A/C on during this initial period of idling. I also always roll the front windows down at this stage. After this initial period, the rpm comes down and settles at around 700 when I turn the A/C on with the front windows still rolled down and gently drive away, soon the auto-lock comes on, and a bit after that I roll up the windows Within a few minutes, the engine temperature reaches 90 degrees and the car can be pushed for a bit of fun or whatever other reason.

During long drives (only one so far), I keep the MID set at the engine temperature so that if there is any overheating I would come to know.

Knowledgable people may suggest, if there is anything wrong with the routine I have described above.

[swissknife]

There have been discussions around this some time earlier. It may probably help answer questions.

http://www.team-bhp.com/forum/techni...html#post17405

[Thad E Ginathom]

AC is a tiny load on the engine compared with... Driving! I don't think it is worth even thinking about. The aerodynamics of driving with the windows open possibly puts more strain on the engine than the AC does.

Also, this is another instance in which the car looks after itself. The AC does not run when starting the engine or for
a minute or so afterwards.

Concerns about AC probably have more to do with it being used as an excuse for higher cab fares that were never really warranted.

Yes, I appreciate that ac is work, and work requires energy, and energy does not come from nowhere. I still think it hardly affects anything.

How about never carrying any passengers because of the strain on the engine?

All of this in my humble opinion only. Ok... Perhaps not so humble

[Guite]

It never occurred to me that engine performance and AC will be related. Now that the topic has been brought up, it still does not bother me. I prefer the convenience of putting the AC always ON.

I have not read the linked thread but my opinion is as follows. My knowledge is limited in this sphere but here I go anyway: the AC compressor must be running on electricity generated by the alternator. Whether the engine is heating up on initial startup or idling at traffic signal, the engine speed required for the alternator to run has been achieved. If it were not the case you would have to shut off AC at traffic signal or rev the engine constantly.

[Thad E Ginathom]

Originally Posted by Guite

It never occurred to me that engine performance and AC will be related. Now that the topic has been brought up, it still does not bother me. I prefer the convenience of putting the AC always ON.

Me too. Auto, recycle, 22.5 --- unless or until passengers complain about being too hot or too cold.

A reminder that we are talking about the VW Polo GT here, and that Climate Control is indeed more than a marketing tag. It is more sophisticated than a simple AC control, even on a lesser Polo model, which is very rudimentary by comparison. As I mentioned before, after starting the engine, the AC does not start until the engine control system is good and ready to let it. The delay is only short.

[graaja]

Originally Posted by Guite

It never occurred to me that engine performance and AC will be related. Now that the topic has been brought up, it still does not bother me. I prefer the convenience of putting the AC always ON.
...

Originally Posted by Thad E Ginathom

Me too. Auto, recycle, 22.5 --- unless or until passengers complain about being too hot or too cold.

A reminder that we are talking about the VW Polo GT here, and that Climate Control is indeed more than a marketing tag...

Totally agree. Even I don't bother turning off the AC. It is always ON, at a temperature of 25 degrees with internal circulation turned on. The only thing I control is the temperature. After all it is automatic climate control!

Not turning on the A/C during cold start may have applied to old generation cars (the topic in reference was started 13 years ago) where the systems were operating asynchronously. But with the latest cars where all the controllers (ECU, BCM, ACC etc) are linked and perform their tasks synchronously, I don't think this is necessary.

As Thad rightly pointed out, the ACC turns on only after a delay (by which time the engine circuit should have stabilized), the ECU automatically takes care of the engine RPM regulation based on the AC load, and A/C is a smaller load compared to driving off.

So I would say leave it ON. It is ACC!

Originally Posted by asitkde

During long drives (only one so far), I keep the MID set at the engine temperature so that if there is any overheating I would come to know.

Knowledgable people may suggest, if there is anything wrong with the routine I have described above.

There is no need of controlling the AC manually. If you notice, even if the AC is kept ON, the blower does not come on immediately after the car starts. It comes ON after a few seconds, and the compressor starts a few seconds after that. This is because all the systems are started up in a sequence. So, I would suggest not to worry about this and leave it in Auto mode and always ON.

Also, no need to worry about the engine temperature during long drives. Even if you do not have the engine temperature displayed on the MID, if there is any problem with the cooling circuit, there will be an error displayed on the instrument cluster which will be very much visible. Just relax and enjoy the drive

[Thad E Ginathom]

Originally Posted by graaja

Also, no need to worry about the engine temperature during long drives. Even if you do not have the engine temperature displayed on the MID, if there is any problem with the cooling circuit, there will be an error displayed on the instrument cluster which will be very much visible. Just relax and enjoy the drive

Absolutely. The time to worry about those things is during the pre-long-drive checks of vital fluid levels. Then we can leave it to the car.

[deetjohn]

OT:

Originally Posted by Guite

It never occurred to me that engine performance and AC will be related.

Oh! You should drive some cars with puny engines. The AC button then becomes the sport button. Push it off for more power to move.

Originally Posted by Guite

My knowledge is limited in this sphere but here I go anyway: the AC compressor must be running on electricity generated by the alternator. Whether the engine is heating up on initial startup or idling at traffic signal, the engine speed required for the alternator to run has been achieved.

The AC compressor is driven directly by the engine using a serpentine belt. The belt and pulley rotates always but the compressor kicks in only when AC button switched on - a clutch engages/ disengages within the compressor.

Many new cars can also disengage the compressor automatically based on the load on the engine - like when you are overtaking.

[Auto freak]

Got myself a Polo TSI a couple of weeks back after canceling our booking for the Vento 1.6 MPI HL. So far very happy with the decision.

It would be great if the long term DSG users can enlighten me on the DOs and DON'Ts I should be following while driving, expecially in congested city traffic.

I have a few doubts that I have listed below.
1. In stop-go city traffic, is it necessary to shift to N every time I come to a halt?
2. If the duration of the stop is relatively longer like in a traffic signal or in a tool-booth queue, should I shift to N every time I come to a halt or can I hold it in D without heating up the clutches?
3. Climbing up an incline: My parking is in the first floor of a building and it requires me to climb up a rather steep slope. While doing it in D, the transmission shifts from D1 to D2 half way through the incline. I'm concerned if the clutches would have sufficient vehicle speed to fully engage in D2 on the incline. Should I be doing the climb in manual mode instead?
4. Sport mode: Can I shift from D to S and S to D while on the move? Noticed that it requires pressing the button the gear stick for shifting from D to S and while shifting from S to D the button press is not required.

Thanks a lot in advance!

[Rajeevraj]

Originally Posted by Auto freak

1. In stop-go city traffic, is it necessary to shift to N every time I come to a halt?
2. If the duration of the stop is relatively longer like in a traffic signal or in a tool-booth queue, should I shift to N every time I come to a halt or can I hold it in D without heating up the clutches?
3. Climbing up an incline: My parking is in the first floor of a building and it requires me to climb up a rather steep slope. While doing it in D, the transmission shifts from D1 to D2 half way through the incline. I'm concerned if the clutches would have sufficient vehicle speed to fully engage in D2 on the incline. Should I be doing the climb in manual mode instead?
4. Sport mode: Can I shift from D to S and S to D while on the move? Noticed that it requires pressing the button the gear stick for shifting from D to S and while shifting from S to D the button press is not required.

Thanks a lot in advance!

Congratulations on the buy.

For 1and 2 if the stop is more than 20-30 sec would be advisable to shift to N. But there have been discussions indicating you don't need to do that. I anyway do it. If nothing prevents an unintentional creep.

For point 3. The dsg very rarely stays in 1. As soon as you start moving it shifts up. But it does drop back to 1 if the incline warrants that. Personally I don't shift to M unless it is a very steep incline and I don't want the dsg to do the 1-2-1 shifting. ( And this is for the heavier vento tsi)

Point 4. Yes you can shift between D and S as and when you want on the move.

[anb]

Originally Posted by Auto freak

Got myself a Polo TSI a couple of weeks back after canceling our booking for the Vento 1.6 MPI HL. So far very happy with the decision.

Congrats. Does your car come with RCD 330 Plus ?

[Auto freak]

Originally Posted by anb

Congrats. Does your car come with RCD 330 Plus ?

It came with the RCD 330G only. I think the 330 Plus comes only with the Vento HL Plus variant.

[aditya9567]

Originally Posted by Auto freak

I have a few doubts that I have listed below.
1. In stop-go city traffic, is it necessary to shift to N every time I come to a halt?
2. If the duration of the stop is relatively longer like in a traffic signal or in a tool-booth queue, should I shift to N every time I come to a halt or can I hold it in D without heating up the clutches?
3. Climbing up an incline: My parking is in the first floor of a building and it requires me to climb up a rather steep slope. While doing it in D, the transmission shifts from D1 to D2 half way through the incline. I'm concerned if the clutches would have sufficient vehicle speed to fully engage in D2 on the incline. Should I be doing the climb in manual mode instead?
4. Sport mode: Can I shift from D to S and S to D while on the move? Noticed that it requires pressing the button the gear stick for shifting from D to S and while shifting from S to D the button press is not required.

Thanks a lot in advance!

Congrats on your buy!
Like earlier mentioned, you don't need to shift to N but it is advisable to do so. The clutches won't heat up as the car recognizes that you're at a halt and cuts off any acceleration. So, for all intents and purposes, it is in neutral. On 3, take a judgement call. If you feel the 2nd gear can take the slope then keep it in D - but I've seen that it is much easier to shift to manual and then stay in 1. The DSG has a tendency to slip the clutch in 2nd gear in D mode.
4 - No problem, you can shift as you please between the two. Requirement of clicking the button to shift from D to S is to prevent accidental movement. If you notice, S to D can be done without clicking the button.

Cheers