Anyone noticed their fuel drains quicker recently?

[AUDI-TDI]

Hello, I have a quick question you guys and your answer would be greatly appreciated. If you’re living in the UK, does anyone else recently realised their car drains fuel quicker than before as supposed to 4/5 months ago?
A full tank on my 1.6tdi diesel used to give me 350-400 miles and now full tank and I’m lucky I’m getting 200 miles. First I thought there’s something wrong with my car so I changed the injectors/ fuel pump/ fuel filter/ MAF sensor all the usual bits that would take a toll on my fuel consumption but I’ve spoken to a few people and they all have noticed the same with their cars. They said it could be with the chemicals/ water added to fuel which shows your car as full but the actual fuel might be 3 1/4 of it. So in essence if this theory is correct, that could be mean there’s nothing wrong with my car in the first place.
i just want to ask other people if they noticed the same issue and it’s not just my car.

 

[miningman]

your neighbour is getting pretty good FE with his truck , but then again he's also getting pretty good with his siphon hose

 

[Tdijarhead]

It’s winter, FE suffers in the winter.

 

[AUDI-TDI]

It’s winter, FE suffers in the winter.

Maybe you are correct but this is the first time I’ve noticed and do bare in mind I’ve owned the car for 8 years surely this would of been noticed years ago?

 

[csstevej]

I’d get a locking fuel cap , as miningman stated “ your neighbor might be getting good with a siphon hose “ espically with what’s going on with fuel prices around the world.
Usually FE does suffer in the winter …I usually loose about 5 miles or so a gallon…about 10% fuel economy hit.
Question ….excluding you dash guage for coolant temp…can you scan what actual coolant temp is either with scan guage or VCDS or equivalent? If thermostat is stuck open your car will not be up to temp but your indicator in the cluster will be fine , they don’t call them idiot gages for nothing . That will severely impact your fuel economy……had that happen to me… Dash read 190 degrees but scan guage was reading about 160….replaced thermostat and everything went back to where it was supposed to be….. just my .02.

 

[AUDI-TDI]

Than

I’d get a locking fuel cap , as miningman stated “ your neighbor might be getting good with a siphon hose “ espically with what’s going on with fuel prices around the world.
Usually FE does suffer in the winter …I usually loose about 5 miles or so a gallon…about 10% fuel economy hit.
Question ….excluding you dash guage for coolant temp…can you scan what actual coolant temp is either with scan guage or VCDS or equivalent? If thermostat is stuck open your car will not be up to temp but your indicator in the cluster will be fine , they don’t call them idiot gages for nothing . That will severely impact your fuel economy……had that happen to me… Dash read 190 degrees but scan guage was reading about 160….replaced thermostat and everything went back to where it was supposed to be….. just my .02.

Thank you for answer. I just plugged in my OBD11 scanner to monitor my coolant temp. My dash said 90 and on the live data from my scanner saying 86 degrees. Is it safe to say my thermostat is fine?

 

[csstevej]

Depending on how long the cars been running and how cold it is at your location, it might be good…..however if it’s been running awhile and in the 40-50 degrees F……then I’d say it’s on the low side.
How many miles / kilometers on your vehicle? Any idea when it was last changed?
If you do decide to replace it I would suggest OEM instead of after market.

 

[AUDI-TDI]

Depending on how long the cars been running and how cold it is at your location, it might be good…..however if it’s been running awhile and in the 40-50 degrees F……then I’d say it’s on the low side.
How many miles / kilometers on your vehicle? Any idea when it was last changed?
If you do decide to replace it I would suggest OEM instead of after market.

Thank you for comment. I don’t notice such difference in going up to 90 degrees in temperature. In the morning it does make me drive 2-3 miles then my car starts to get to temperature and once I start to see the gauge move, then shortly after it’s at 90 Degrees. My 1.6tdi VW engine has done 180k miles and if I’m being honest with you, I don’t think the thermostat has ever got changed. Nor has my o2 sensor. Maybe that is the reason why my car drinks too much. I’ve spent soo much already on new injectors and sensors and everything but still drinking soo much fuel.

 

[csstevej]

Your o2 sensor should be fine…..otherwise you’ll be getting a code for that.
I would change the thermostat for piece of mind and see if it makes a difference……but that’s me.
If you do your own maintenance it shouldn’t cost much….if you bring it to a shop….then it’s a different story…but not a deal breaker….. normally when I do my TB jobs I try to change the thermostat and related pipe at the same time…..coolant is already drained out and it only takes about 10 minutes at that time….

 

[AUDI-TDI]

Okay, I’ll order an OEM one now and will update this post when I’ve fitted it and done few hundred miles test

 

[miningman]

hows your neighbour doing these days with oil at $100 per barrel???

 

[Gingagolfs]

I’m getting same sort of issue, (2.0 tdi cffb) I fill up and trip says 550miles drive 5 mile steadily and trip will say 500 miles ! can watch gauge drop rapidly just sat there or driving steady where as before I’d be getting good fuel economy (no loss of power)
Full scan no issues bought up

 

[AUDI-TDI]

I’m getting same sort of issue, (2.0 tdi cffb) I fill up and trip says 550miles drive 5 mile steadily and trip will say 500 miles ! can watch gauge drop rapidly just sat there or driving steady where as before I’d be getting good fuel economy (no loss of power)
Full scan no issues bought up

This is exactly my problem. I don’t seem to know what’s going on. I’ve changed my injectors, fuel pump, MAF sensors, Fuel Pump relay. Crank and campshaft sensors

 

[Gingagolfs]

This is exactly my problem. I don’t seem to know what’s going on. I’ve changed my injectors, fuel pump, MAF sensors, Fuel Pump relay. Crank and campshaft sensors

Do the engine coolant temp sensors send two signals, One to dash and one to ecu ?
clutching a straws now it’s doing my head in

 

[csstevej]

The coolant temp sensors in MKIV have two sensors in one housing , one goes to ecu the other to the dash.Not sure on the MKVI. Need to reference a wire diagram.