1.8 16v Poor fuel economy

[Andy 16v 0]

Hello Ladies and Mentalmen!

 

My car is a thirsty machine; I've had it 'tuned' at a bosch centre recently and they said the car was set up fine and everthing was spot on. Annoyingly though she still smells like she's running rich and the best i've had on a run is around 26 mpg. In English it's costing me the best part of £25/30 notes for my 100 miles a week I do.

 

Does anyone have any suggestions what I can look for or any idea why she's so thirsty?

 

Thanks guys!

[Wendy 0]

I think more information is required -

 

How many miles per day is that you are doing?

If only 14 per day, 7 miles per trip the car is only just warm, if that was in heavy traffic too - that would probably be about right I would have thought

 

Are you in heavy/light/No Traffic ?

 

Are you letting the Oil temperature reach 80 degress before opening the car up ?

 

I will let the Mentalmen ;-) provide the more technical side of an answer.

 

By the way - calling the car a 'She' - is for when she is behaving and a 'He' when misbehaving !!!!

 

Besides that would be good for a VR !!

[Andy 16v 0]

I refer to the car as a she because, like females, she's a pain in the backside.. :)

 

I only do around 10 miles a day normally so I understand the poor return as the engine will still be cold. But, when I've been on a run along the motorway, like my trip to Leeds last week, it wasn't any better.

 

I'd be better off with a VR but I've just spent a good few quid on this and the Liverpool postcode isn't good for insuring a VR6 thanks to our darling thieves.

[Wendy 0]

I refer to the car as a she because, like females, she's a pain in the backside.. :)

 

 

Maybe - but you keep going back for more - like most men !!!! :-)

[craigowl 0]

Yes, my VR6 does 24mpg at worst in stop/start/urban and 31-37mpg on long runs mixed with some urban. A happy engine!

[retroraddo90 10]

mines doing between 20-25mpg locally and most i had was 34.2 on an eco drive lastnight. i thinks its pretty normal to be honest mate

[davidwort 0]

When you say 'tuned' was that actually on a rolling road or did they just set the idle CO?

A 'healthy' 1.8 should see about 30mpg average, possibly more when the weather is warmer, on a long motorway run at around 70mph it should easily make close to 40mpg, short runs around town in the cold will kill mpg though.

 

Things to answer/check:

what tyres and pressures are you running

are the brakes binding at all

is the wheel alignment correct

how old are the injectors

when was the fuel filter last changed

is the fuel pump noisy or warbling

air filter clean? plugs, leads etc all in good nick

is the engine and ignition timing set up correctly

exhaust leaking, baffles broken?

 

a rolling road session (probably only about 60 quid for an hour run) will provide a torque plot that can help diagnose any engine issues, it's easy to pick up 5-10 bhp and a similar amount of torque from setting a 16v up properly, which can equate to several mpg in efficiency from the engine pretty easily.

[Lee Rees 10]

Thanks for the reply. I'll look out for a 2.0 8v corrado.

 

By the way I don't mean to sound like a troll but the info I got was from wikipedia:

 

1.8 L I4 115 hp

1.8 L I4 16-valve 123 or 139 hp

1.8 L I4 Supercharged 158 hp

2.0 L I4 16-valve 134 hp

2.8 L VR6 178 hp

2.9 L VR6 192 hp

[Andy 16v 0]

Thanks for your replies everyone!

 

Davidwort; my fuel pump is very noisy and I've never changed the fuel filter in the four years I've owned the car. Could this be an issue?

 

Cheers!

 

---------- Post added at 3:12 PM ---------- Previous post was at 3:11 PM ----------

 

Thanks for your replies everyone!

 

Davidwort; my fuel pump is very noisy and I've never changed the fuel filter in the four years I've owned the car. Could this be an issue?

 

Cheers!

[Wild-Animal 0]

Yeh I would be changing your fuel filter. It could be causing a strain on your fuel pump

[Andy 16v 0]

Is that located in the tank?

[james153 0]

The filter should be on the outer tank pump under the offside rear seat (accessed from the underneath.)

 

Just while we're on this thread, i have a 2.0 16v and on a totally motorway run at 75mph i get 34mpg at best, and more like 22 across town;

tyre pressures are fine, new filters all round, injector spray patterns look fine. what sort of noises will the fuel pump make if it busted? Anything else i should be aware of?

 

Cheers for the help