Poor mpg, low temp

[DomP182]

I've noticed my mpg has got pretty poor, around the low 30s and my temperature gauge sits a bar sometimes two below the halfway that 1*2s always sit at.

Is this a fault thermostat, CTS or both/neither?

 

[Patrick Bateman]

Likely thermostat I'd imagine.

Is low 30's poor though? That typically what I've got in 5+ years of ownership.

 

[JamesBryan]

Can be both.

Have you got a way of reading the coolant temp via OBD?

 

[DomP182]

I used to get high 30s even 40 on my 20 mile work commute, no town driving. My ph1 was even better

 

[DomP182]

Can be both.

Have you got a way of reading the coolant temp via OBD?

No I dont think my cheapo OBD does that

 

[imprezaworks]

Do you get heat in the car? I would say a sensor.

 

[DomP182]

Do you get heat in the car? I would say a sensor.

Yeah I'm getting heat, I'm going to use it for a sneaky few days away in Snowdonia so it will be interesting to see what mpg I get on that run. The thing that I noticed first was the needle below half way, all 1*2s I've had were bang in halfway

 

[JamesBryan]

I would edge towards it being the CTS.

Thermostats usually fluctuate up and down when a bit dodgy.

 

[DomP182]

I would edge towards it being the CTS.

Thermostats usually fluctuate up and down when a bit dodgy.

Easier swap too

 

[JamesBryan]

Easier swap too

Yeah shouldn't lose any coolant if it's stone cold really.

 

[DomP182]

I remember changing one on my Valver years ago because it wouldnt run properly from cold

 

[Amos91]

No I dont think my cheapo OBD does that

if you’re using a Bluetooth obd with the torque app you can read coolant temps.

I would side on it being a stuck open thermostat personally.

 

[DomP182]

if you’re using a Bluetooth obd with the torque app you can read coolant temps.

I would side on it being a stuck open thermostat personally.

Might get a bluetooth obd reader then, any recommendations?

 

[Amos91]

Might get a bluetooth obd reader then, any recommendations?

Any Elm327 Bluetooth adaptor will do from eBay. Then the torque app on Android.

 

[DomP182]

I've bought a bluetooth obd reader just now so woll have a look when it comes

 

[davo172]

Change the sender and stat cheap and easy to do that will sort it

 

[R3k1355]

Change the sender and stat cheap and easy to do that will sort it

This exactly, just do both.

 

[DomP182]

Change the sender and stat cheap and easy to do that will sort it

I'm Herefordian, if it ain't broke... that said if I had more spare cash I'd be replacing everything possible from RPD

 

[Stevej172]

@DomP182 but then if you do a long run over a weekend and get low MPG, surely you would save most the cost of the parts in using less fuel???

 

[DomP182]

@DomP182 but then if you do a long run over a weekend and get low MPG, surely you would save most the cost of the parts in using less fuel???

That's a good point but it's the 172 or our Tiguan up to Snowdon, I cant resist a blast up there in my car. The thermostat/Cts can wait

 

[Ol’ Tarby]

It's about 35 quid for both ain't it?

 

[DomP182]

It's about 35 quid for both ain't it?

£63 from RPD

 

[JamesBryan]

It's about 35 quid for both ain't it?

£30 each roughly.

 

[Ol’ Tarby]

£30 each roughly.

Sod that, cheap stat from ECP for 4 quid 🤣🤣

 

[DomP182]

Got the bluetooth obd reader and downloaded Torque lite. Fair to say I dont understand a lot of the readings it gives or their relevance. Is there a guide anywhere as to what they should all be?

I can see it will be useful though, how accurate is the mpg average etc?

 

[JamesBryan]

Got the bluetooth obd reader and downloaded Torque lite. Fair to say I dont understand a lot of the readings it gives or their relevance. Is there a guide anywhere as to what they should all be?

I can see it will be useful though, how accurate is the mpg average etc?

On the home screen, go on Realtime Information.

Mine loads up a page with dials on by default it has things like RPM, throttle and coolant temp.

Do yours look similar?

 

[DomP182]

On my phone there is no home screen of preloaded dials, I had to put my own on. Also cant see realtime information, should I get torque pro instead

 

[JamesBryan]

On my phone there is no home screen of preloaded dials, I had to put my own on. Also cant see realtime information, should I get torque pro instead

Could be different, mine is the pro

 

[MRBILLYUK]

Could be different, mine is the pro

View attachment 1454835

View attachment 1454836

I have pro too and that's how mine looks.

 

[DomP182]

Just downloaded the pro version, I'll have a play tomorrow

 

[DomP182]

When should it go from closed loop to open loop?

 

[JamesBryan]

When should it go from closed loop to open loop?

Within a minute or two from cold i'd imagine.

 

[DomP182]

I dont understand half of the stuff that is recorded to be honest, hp but no bhp?

 

[JamesBryan]

It's the other way round too, it starts at open loop and then switches to closed loop when the lambda warms up.

Then back to open loop after 5000rpm.

 

[DomP182]

It's the other way round too, it starts at open loop and then switches to closed loop when the lambda warms up.

Then back to open loop after 5000rpm.

Yes that's what it's doing so that's good.