ECU Upgrade Appreciation or Problems

[blutopless2]

have my 08 Jetta TSI done with APR.

Have not switched programs since having it done. Much improved response down at low speeds and improves the unnerving lag from a standstill.
Fuel consumption i now average about 8L/100k's mixture of freeway and suburban - pre chipping was about 9L/100k's. Freeway consumption can be down to 7.5L/100k's.
Even tho i dont flog the car to use all the extra power etc i think it just improves the whole driveability of the car. Its just nicer to drive.
I have not experienced any problems with the car since the chipping was done.

[G-rig]

I doubt a retune is more economical (certainly isn't when you put your foot down). It would come down to your driving style. I don't see how it can make more power using less fuel, unless more air generates it.

Good not to switch programs while driving (and it's advised against in the manual), could be a few of the problems the other chap is having?

[blutopless2]

I doubt a retune is more economical (certainly isn't when you put your foot down).

Have only put down here what i have experienced and explained why. If you doubt it then talk to someone like Guy H who can probably confirm what i put down. I'm sure this is stated on the APR website.
I was sus about their claim for better fuel economy also.

I don't see how it can make more power using less fuel, unless more air generates it.

you're right... more power means more fuel... but there is also the torque to consider here not just raw kW.
AFAIK the added economy that you can get comes from shifting the torque curve further down the rev range.

[G-rig]

Have only put down here what i have experienced and explained why. If you doubt it then talk to someone like Guy H who can probably confirm what i put down. I'm sure this is stated on the APR website.
I was sus about their claim for better fuel economy also.

Not saying you're wrong but will have to ask him. May help writing down the km and litres/distance as well as i'm not sure if its exactly the same as the MFD reading.

I know a lot of people including myself have noticed you don't have to press the pedal as hard for the same power & also know they are detuned from the factory but i'm willing to use more fuel for more power as are most people.

[John Deere]

My fuel economy when driving to and from work is slightly improved....from about 8.2L/100 average to 7.9L/100 average. This comes from not having to press the go pedal as much to go up small rises etc. as a result of more low end torque.

At the track its a different story, about 29L/100 with the chip (didn't track it without though)

[blutopless2]

Not saying you're wrong but will have to ask him. May help writing down the km and litres/distance as well as i'm not sure if its exactly the same as the MFD reading.

i worked out my fuel consumption using the calculation method several times doing different styles of driving etc both before and after the chipping... All of the times i have done it it returns the same values as my MFD. I know that people have varying degrees of success with the MFD values but mine seems to be spot on.

On a trip to Queensland in March this year we travelled around 4500km's. The average fuel usage was around 7.8L/100k's. The best i got was on purely freeway driving of course at 110kmh, returned 7.5L/100k's which really surprised me considering we had 3 adults, toddler and a boot chockablock full of luggage.

[jimbomort]

I doubt a retune is more economical (certainly isn't when you put your foot down). It would come down to your driving style. I don't see how it can make more power using less fuel, unless more air generates it.

Speak to Guy at APR or see details in Tuning thread on Tiguan forum, but it is possible and, as I understand it, primarily for the following reason - if the mapping is done for a specific RON (like 9 then the engine will run on that more efficiently than on the factory setting that takes a wider range of RONs into account and therefore cant run as efficiently on a specific RON. The other possibility (and I am posturing more here) is as some have already suggested related to the change in the torque curve. Engines are more fuel efficient under high load (ie more load at lower revs - to a point) as friction etc losses effect efficiency as revs climb.

Of course if you use the extra power , especially on boost/at higher revs then yes, you dont get to use that extra power from the same engine without using more fuel. Not quite the holy grail of more power and better fuel economy all round, but damn close - more power when you want it and better fuel economy when you dont.

[jimbomort]

On a trip to Queensland in March this year we travelled around 4500km's. The average fuel usage was around 7.8L/100k's. The best i got was on purely freeway driving of course at 110kmh, returned 7.5L/100k's which really surprised me considering we had 3 adults, toddler and a boot chockablock full of luggage.

For all its worth I have got 6.9l/100klm on longer trips with a roof box on and the car loaded to the hilt out of our Tiguan 125 2.0TSI. Have also got down to mid 6's on a number of occassions. True this has been driving with a focus on economy, but given the Tig is both heavier and higher than the Jetta, I'd be surprised if you cant get down to the mid 6's with the Jetta. If you are interested in getting more economy out of your car on cruiser trips - check out Greenfleet - they have some good tips on driving economically. Either way sure the chipped Jetta is lots of fun.

[G-rig]

Speak to Guy at APR or see details in Tuning thread on Tiguan forum, but it is possible and, as I understand it, primarily for the following reason - if the mapping is done for a specific RON (like 9 then the engine will run on that more efficiently than on the factory setting that takes a wider range of RONs into account and therefore cant run as efficiently on a specific RON. The other possibility (and I am posturing more here) is as some have already suggested related to the change in the torque curve. Engines are more fuel efficient under high load (ie more load at lower revs - to a point) as friction etc losses effect efficiency as revs climb.

Makes sense, as long as you drive it the same as before which most people don't having the extra power (and boost). I have the APR R32 N/A tune and don't think it uses any more fuel as I know these euro cars are detuned to opperate in a host of operating conditions.

[parso_rex]

If the remap modifys ignition timing (assuming it was not optimised) and/or leans out the fuel mixtures then you would use less fuel for the same power/torque output. Its pretty common to lean out the mixtures as most manufacturers supply them notoriously rich exfactory. The reason they do this is mainly as a bonus safeguard as the charge temp is reduced with damage to the internals being less likely should you be experiencing a problem. The rich mixture doesn't hurt power too much either - a little but not something worth deliberately chasing unless your after every last kW. It doesn't do wonders for spark plugs or oil though

M