Fuel economy better in Manual Mode

[POLARBEAR666]

Has anyone else found that fuel economy is significantly better in manual mode.
I do the same drive twice a day for an hour. On that trip I normally got 7.7 or 7.5/100 on the trip meter at the end of the trip.
For the past few trips I have been driving totally manual mode and getting 6.5, 6.6, 6.6, 6.4.

IN DRIVE I think that on the 1.4 TSI this is because the car in Drive wants to rely on high boost and high gearing. EG 6th gear with boost being used to speed up when needed.

VS

MANUAL MODE I rely on rev's and low boost. EG sitting in 2nd or 3rd at low throttle and only changing up when I pass 2200-3000 or revving slightly more at low throttle input.

I think that driving around relying on lower gearing to provide the acceleration is far more fuel efficient than the way Drive mode changes up to the highest gear possible as soon as possible and then uses LOTS OF BOOST to get going because in reality it is out of the ideal gear. Boost must be using far more fuel than simply having higher revs at a lower throttle input.

Thoughts?

[Paul_OH]

I've experimented a bit and came up with the around the same figures (using M or D) +/- 0.2l/100km approx. I do the same drive each day approx 40km each way mostly highway speeds but broken up with traffic lights, light-medium traffic and can hardly tell the difference. If I have a glint in my eye I use M, if I'm enjoying good music I'm in D, if I feel like screwing the planet I'm in S... 'S' for Sheesh, that revs a lot! Not really, I find S next to useless.

[tinto]

Interesting... I'll have to give it a go.
Although I only tend to use manual /paddles coming up to a corner.. cracking down 4 gears so i can roost on boost(tm).
The rest of the time i'm in slackjaw, mouth-breathing D mode.

I've always thought the methods DSG used were pretty efficient - changing way earlier than i would in a manual. It never seems to be labouring.
Your finding is that it could sip less a few hundred RPM up?

My other thought is this thread is about to be inundated by oilers in non DSGs talking about their fuel economy and best brand of acousti-blok ear plugs.

[Paul_OH]

My other thought is this thread is about to be inundated by oilers in non DSGs talking about their fuel economy and best brand of acousti-blok ear plugs.

Hahaha, C'mon Cogdoc, we're ready and waiting

In all seriousness though I do find it 'feels' more efficient off boost higher in the rev range with not boost than lower down with that pesky whine. It's been a while so I will have a play and see what I can do. I must say though that since getting my stereo upgraded it's done my economy a lot of good as I'm happy just to cruise along somwhat.

[tdi guy]

Not my experience so far (17000km).

In D I average 7.7km/100 and when I experimented in Manual I watched the consumption rise steadily. Not scientific, but my perception is that Manual is less fuel efficient that D. I tend to 'blip' the throttle briefly at low revs to 'kick down' so perhaps that helps the average consumption in D (less time spent labouring below 1500rpm).

"S" is higher, of course (given it changes up over 3000rpm, compared with about 2100rpm for D).

TG

[dangerous_daveo]

I need some good ear plugs for the bike actually...

Which gets about 2.5L per 100kms just while we are braging :-p

I found D to be best. I get lazy and forget I'm in manual mode, and I don't hear the engine cause the stereo, people start looking at me funny cause I'm sitting on 6k... It normally twigs then. That or I drive very very differently in manual mode. Either way, going to work and back, it isn't a good idea for me.

[POLARBEAR666]

I have worked out why on the TSI with my driving style it is more fuel efficient to be in manual.

It is because I am using CONSTANT LOAD driving (eg staying around 2000rpm and changing gears as appropriate to maintain that).

Whereas, the Drive program is doing CONSTANT GEAR eg stay in 6th as much as possible and let the boost vary to get car going.

Constant load driving is more efficient for my car than puttering in 6th and constantly having to kickdown to 5th or pile on lots of load and boost in 6th to keep moving.