1.6TDI BMT 105 - Slow and thirsty?

[TDiBoraSam]

Morning all!

I've been driving a Golf TDI 105 BMT for a few months now (I inherited it), and so far I have to say I've found it to be very slow, gutless and rather thirsty.

Is this normal for this car?!

Average mpg seems to be about 53, if driven carefully. Normal driving yields about 47-48, which I consider appalling for a supposed 'eco' car. I was previously driving a BMW 120d, which was a heck of a lot faster (obviously), but even when pushed hard would only drop to about 46mpg, whilst normal driving returned about 58-60mpg. I'm talking about the same return journeys to and from work each day, and my driving style is neither aggressive nor delicate, just 'normal'.

If ever there was a car crying out for a remap, it's my Golf, but I'm just not convinced the clutch would take it! It already suffers from pronounced clutch judder if I change up through the gears when the gear change indicator tells me to, particularly in 4th and 5th - I have to let the revs go higher before changing up. Also it appears that the gearing isn't set up very well. Often the revs are too low for, say, 3rd gear, but dropping to 2nd causes the car to lurch because the revs are then too high for that gear.

All in all, apart from cheaper tax and insurance, I have been pretty disappointed with the Golf compared to the BMW. It just isn't as driveable, and I dread having to stop and then get it going through the gears again, which is so laborious. I was hoping the Golf would be just a steady, easy to drive, economical car.

Does anyone else have a similar experience?

[J400uk]

That MPG sounds normal to me, and I've seen the clutch judder you describe before on these.

A couple of my friends have the 1.6 TDI and I've got the 2.0 TDI. They all do thereabouts the same MPG. It seems the bigger engine and 6th gear in mine means it isn't working as hard, so still returns the same economy.

[Gollings]

Doesn't sound right to me. I've got a 1.6 BMT that returns mid-high 60's if driven carefully. That's a brim to brim calculation as the trip computer underestimates by about 12%. In fact a recent tank full gave 71mpg but that was a lot of motorway driving. No clutch judder and it has 85k on the clock.

[Dai Roberts]

Does sound low to me I get 60-63mpg nearly all the time and long motorway drives improve it considerably. Obvious to say but if you put your foot down the MPG goes down, my friends say I drive like a granny.

Warmer weather improves MPG a bit for me. There are lots of possible reasons - serviced properly? tyre pressure, still have eco tyres? extra weight.
The gearing is a bit odd to start with but you get used to it and using the revs about 2k where the power is, changing up later is the only way to go.

Saying all that I do wish I had gone for the 2 litre version.

[TDiBoraSam]

Thanks for the replies!

Yes, it has good tyres. 2 x original Michelins and 2 x Goodyear EfficientGrip Performance, all at the correct pressures. Not carrying any extra weight. Fully serviced.

It seems that anything over 60mph, and the mpg starts dropping off considerably, and you can't tootle along a motorway at 55!

The most annoying things are that 1st gear is just flat/dead, and when the clutch bites (when going into any gear) the car judders/shunts. Same happens when in gear and I completely release the accelerator and then re-apply some power - as the torque goes to the clutch, there's a judder. It just doesn't feel like a smooth runner. Trying to crawl along in traffic in 1st gear is impossible because the car just wants to bunny hop, so I end up riding the clutch to keep a smooth motion going.

As an aside, I have enquired in several places about remapping the 1.6TDI. Invariably I get told that the engine is good for 140-145hp, but without any scientific proof to support the figures. However, I enquired with Oettinger Sportsystems in Germany, and they will only remap the 1.6 to 125hp. If anyone knows what they're talking about, it's these guys! So, be careful what you go for if tempted to remap!

[Alex5555]

Usually when I have such high mpg I drive for about one hour on motorway to clear exhaust system(particle filter?) even though never had engine management light on indicating blockage. But I see that you done it, not sure for how long though

[zollaf]

sam, have you tried just thrashing the nuts off it. you say you inherited it, so i presume an older person had it before, am i right, drove like miss daisy. poor thing might just be crying out for a very good italian tune up with some expensive diesel to clear its throat out before it will drive properly. might also sort te clutch out as well.

[TDiBoraSam]

Yes, it's had a couple of thrashings, but it's doesn't make any difference. It was driven in a careful, but 'normal' manner previously. Usually on 40-50 mile round trips 5 days a week.

I wasn't expecting it to be quick by any stretch of the imagination, but compared to the BMW 120D I had before, it's the economy and driveability that is really disappointing. The Golf is lighter, lowered powered and set up for economy, but yet comes nowhere near the mpg I was getting out of the BMW, which had 177bhp and pulled like a train! Is it just that the BMW has a far better engine?!

As for the clutch judder, well, this is one of the things putting me off having a remap. Nobody seems to know what torque the standard clutches are rated to anyway, and given that mine judders with standard power going through it, I can't see it taking any extra power!

[Buzzoff]

maybe sell the care dude and go for another beemer!!!
After all its a 1.6 diesel, you reall can't compare the two cars as they are two dotally different vehicles.

I think you gave me some advice the other day regarding a re map, so maybe take my advice and either live with it or maybe just move on to something that you will be happier with.

Regarding the mpg figures my 2.0L BKD 140 Mk5 Golf with 175K miles on the clock returns a real world 58-60mpg all day long. Some times the "Bluemotion" thing is not quite a good as you may think.

[J400uk]

Yeah selling it might not be a bad shout. The 1.6 TDI BMT is at least fairly desirable on the used market as lots of people buy them under the illusion of economy and low running costs :D

[TDiBoraSam]

Thanks for the replies guys.

I know I can't directly compare the Beemer with the Golf. I was fully expecting it to be slower, but I thought that it would be a step up in fuel economy.

Anyway, after a lot of searching and asking lots of technical questions, I have found a tuning company in Cheshire who are going to remap it for me next week. Full custom remap, rolling road before and after, and they'll remove the map and put it back to standard if I don't like it. So, I figured it's worth a go to see if it improves the way the car drives. If it does, I'll happily keep it, but if not, I'll remove the remap, sell it and go back to a Beemer.
The company I've chosen were the only ones who directly answered all my technical questions, and were happy to tell me exactly what they will alter as they do the remap. Expected to take about 3 - 4 hours to do.

I will post again to let you all know how I get on!

[Dai Roberts]

silly but - MFD set to US gallons?

[TDiBoraSam]

Well, I've cancelled the remap. I contacted both Garrett, who make the turbo, and Sachs who make the clutch. Sachs have said that an increase in torque of over 10% will be asking for problems.
The remapper said that a torque increase to 320nm would be fine (250nm standard), however Sachs state that the standard clutch will definitely not take 320nm and will fail quite quickly.

Glad I did a bit more research. When I spoke to the remapper they sounded very knowledgeable and convincing, and told me they would essentially be unlocking untapped power and fuel maps that are already on the ecu, but disabled by VW. But, if the clutch will almost certainly fail within a short time, it just goes to show that remapping really is still a black art, and these figures they quote aren't really within the limits of all the components and aren't derived scientifically.

I await a reply from Garrett. I cannot find any info on their website about the GT1236V turbo, which is fitted to the 1.6TDI.

So, remap by all means, but expect to have to upgrade the clutch, and maybe expect premature turbo failure. Lesson learnt...a small tuning company cannot provide a better fuel map than VW.

[Buzzoff]

Dude,

I think your wise not to do the re map.

Enjoy it for what it is or maybe sell it and buy another vehicle.

Either way good luck dude and thanks for your posts.

[TDiBoraSam]

Just to conclude the 'Thirsty' element of the thread.

I have done a manual calculation of mpg between fill-ups and found that the onboard computer is under-reading mpg by approx 12%!

Going off my calculations, the car has is managing an average 61 mpg, which I feel more happy with.

So...less thirsty than I thought, but still slow. From my remapping research, there doesn't appear that much can be done to reliably remap the 1.6TDI without upgrading the clutch.

But...for my lay person's brain, could someone please explain how the new Passat 1.6TDI is 120hp, but still has only the same amount of torque as the 105hp (184 lb/ft).

Why do all remappers only increase bhp whilst massively increasing the torque too? Could the bhp be increased whilst leaving the torque the same, and would it be worth doing, if it could be done?

[J400uk]

Thats very strange as usually the computer over-reads! I think that behaviour can be 'corrected' in VCDS

RE the Passat 1.6 TDI having 120PS, its an all new engine (EA288). So its just a coincidence the torque is the same as the old Golf 1.6 TDI 105.

[MojoVeeDub]

Hello

Personally I wouldnt remap a bluemotion or an eco version. I have the 1.6 tdi (non blue motion) and can identify the clutch judder and the bunny hopping in first.

I put on bigger wheels and alloys and still manage a good mpg. I do 100 miles a week motorway and then crawl to work on the motorway so i make sure it gets a good thrashing to clear the particle filter. It sounds like youre really unhappy with the car dude, id sell it and buy again

I drove both the blue motion and the standard tdi and found the BM a less enjoyable drive. It reminded me of a quad with a limiter on it. Just felt like there was more to give but it wouldnt give out

[Mmalkie]

Having went from an 03 plate 1.6, 16v to 55 plate Mk4 1.9 SDI Estate & struggling to get 470miles/tank, I decided after 20k miles &13 months ownership, that a trade in was required. So a year ago, a young salesman talked me into a trance, bent me over a table & beat me senseless, quoting figures of 75mpg & zero tax & got me to sign up to my 10 plate Mk6. Needless to say the best I've seen is 60mpg on a single trip down in the borders, as it was nose-to-tale contra flow roadworks.

Yes I have managed the golden 600 miles/tank, but it took a lot of self control & sitting at 60mph. I have contemplated taking it to the local rolling road & getting the map faffed about with, but I'm not sure the purse string will stretch that far with my impending T25 purchase. I'm not a complete lead foot & i'm no grandpa George sitting at 60 in the middle lane, but pootling about above 80 is only for the overtaking option when there's a queue sitting hogging the lanes. Anyway, cheap Asda diseasel & a bottle of REDEX once a month. Fuel figures took a hit when the DPF refresh hit me at 40k, but it's been fine since & I'm just thru the five 5's




http://badges.fuelly.com/images/smallsig-uk/301311.png (http://www.fuelly.com/car/volkswagen/golf/2010/Mmalkie/301311)

[Seboni121]

Here in the UK there are several companies doing maps for these engines, many have done this engine in the fabia
shark I think is the one that's got more / better results

[manic222]

Have you thought about re-mapping the EGR valve. This should get more power and more economy. You don't have to eliminate the EGR all together just map it so the exhaust gas doesn't switch in as often/as much.

[iscom]

I have had my 2012 golf 1.6 106 BMT tech match dsg for about 3 months and its certainly not slow I thought the 62mpg + when i first drove the car was very good but now its over 72+ mpg according to the Average MPG