Fuel consumption issues

[leej666]

I just recently got a new remote key & fob coded to my car to replace the lost original. Had it professionally done by an authorized company. The key works & remote locks/unlocks etc
However, when I got the car back I noticed that my MFD had been reset. Clock, trip, fuel consumption etc. etc.
I drove the car out assuming that the car had been reset/battery disconnected for some reason
I now noticed that the fuel consumption has gone through the roof? In normal driving I was averaging 5.5-7lt/100km but this has gone way up. When I dropped the car off the estimated range in the tank was 580km. When I got it back it was 270km. Under medium acceleration the consumption is going up to 30lt/100km where before it would go to 12-15lt
My idle is also double as has the motorway consumption average when not accelerating much
I brought it back but was told the computer was reset for programming the key and that it would have to "learn" the averages & driving style again etc.
Having completed only 65kms/40 miles I have used over 1/8th of a tank. The car was returning about 8-900kms to a tank
Anybody had this issue or know is it somehow possible to affect the fueling by coding in a new key? Can it affect ECU settings or injector timing?

Car is a 2005 MK2 Leon 1.9TDI 5spd manual

Thanks

 

[Paddy]

Not had the issue... But think it's important to remember that the reprogramming hasn't impacted your 'fueling' at all - it's merely knocked your guestimations out. As they guy you've spoken to has said; give it a tank or two to readjust and learn how much fuel you're actually using per gallon etc...

 

[leej666]

That's what I was guessing but the tank level gauge is what's throwing me. I wouldn't rule anything out with VAG wiring systems! I'll give it a tank or 2 as you suggest and post results

Cheers

 

[Dan FR]

You can not rely on the range estimation alone. Give it one tank, and calculate the MPG fro mthe distance covered and amount of fuel used.

Does seem odd that its been affected that much though