Help diagnose me a problem

[Graeme4130]

Hi all
I've noticed recently that my 55 plate mk5 gti 5dr has developed a bit of a thirst
Now it's never been particulary frugal, but my normal 30mpg av has dropped to around 25 over the same journey/conditions
Also, my radiator fan seems to come on at random times and the heaters not particulary hot
Someone mentioned this might be a fault of a temp sensor somewhere that's cause the engine to run rich and mess with the cooling system
Anyone shed any light on this please
Any help would be greatly appreciated

[richw911]

Any fault codes?

[Graeme4130]

I'm not sure, can I look this up without diagnostic equipment ?

[richw911]

I'm not sure, can I look this up without diagnostic equipment ?

You can with vag com or a code reader 

[bez101]

does your temp gauge get up to 90 ?
could be the cts or the stat
but id scan it for faults 1st b4 spending on something you may not need

[Graeme4130]

Yeah, it gets up to 90 no probs
It's down on power too, which seems odd. Possibly an effect of ever fuelling
I'll try and book it into the dealers for them to take a look on diagonostics

[Hurdy]

Could be a number of things! Boost leak, turbo gone, dv with a ripped diaphragm.. All would lose you power and as a result increase petrol consumption.

[Graeme4130]

I'm hoping it's nothing too serious as the loss in power isn't consistent, and I'm fairly certain a boost leak would show up as a warning light from the pressure sensor...

[chrisowen85]

My boost pressure sensor went and that didn't show a warning light, I only found out what it was from scanning the car, you would be suprised at how much can go wrong without a warning light coming up on the dash.

[Graeme4130]

Sounds expensive, bugger
Oh well, I'll need to get it fixed as it's up for sale soon to make space for an B7 RS4 Avant - If it's something big like it could be, then at least the warranty will cover it.
I'm gonna miss it though, it's been a great car and besides rear Brake light bulb going  (Which the dealer quoted me £40 to repair and I found the part number, ebayed a bulb for £2.70 and spent 5mins changing myself) this is the only issue I've had with it..