Sintra 3.0 mpg

[Chris Peacock]

We use the car on shortish journeys mostly and the driving is a bit stop start. At the moment wer're averaging around 18 mpg which aint good, and that's driving quite carefully. Does that sound about right? I did read somewhere before that if the lambda (sp??) sensor has gone that can cause bad mpg figures, is there any way to tell if it's faulty??

Cheers, Chris

 

[malcolm]

We use the car on shortish journeys mostly and the driving is a bit stop start. At the moment wer're averaging around 18 mpg which aint good, and that's driving quite carefully. Does that sound about right? I did read somewhere before that if the lambda (sp??) sensor has gone that can cause bad mpg figures, is there any way to tell if it's faulty??

Cheers, Chris

The oxygen sensor can be tested to check its overall integrity, as a bad sensor won't always set a fault code. For detailed instructions follow the link:
http://forums.delphiforums.com/cartune/messages?msg=38.1 You can sign in as a guest, which will allow you to read posts, but not write any.

 

[Mike (2)]

a tech2 link up at your local vauxhall dealer for about £10-15 will tell you. i have a 2.2 16v cd, get about 25-30 in your conditions. i find the super unleaded better (97 octane?) rather than just unleaded gives me more (30-35) but for the price, just about works out the same as such....

we got about another 5-7mpg by changing the fuel filter

tried that?

mike

 

[AstraVanMan]

We use the car on shortish journeys mostly and the driving is a bit stop

start. At the moment wer're averaging around 18 mpg which aint good, and that's driving quite carefully. Does that sound about right? I did read somewhere before that if the lambda (sp??) sensor has gone that can cause bad mpg figures, is there any way to tell if it's faulty??

To be honest that sounds about right - it's a big heavy vehicle being powered by a 3 litre V6 engine. All depends exactly how stop start your journeys are, but if it's a lot of short journeys (<1 mile) then I wouldn't be at all suprised by this. Maybe a good service is in order - new air filter, fuel filter, oil and filter change, but at the most I'd expect 22-23mpg for that sort of driving, so I wouldn't say there's much wrong with it if I'm honest.

Peter

 

[Chris Peacock]

To be honest that sounds about right - it's a big heavy vehicle being

powered by a 3 litre V6 engine. All depends exactly how stop start your journeys are, but if it's a lot of short journeys (<1 mile) then I wouldn't be at all suprised by this. Maybe a good service is in order - new air filter, fuel filter, oil and filter change, but at the most I'd expect 22-23mpg for that sort of driving, so I wouldn't say there's much wrong with it if I'm honest.

Peter

Cheers, was serviced about 1000 miles ago so should be nothing needed doing. I don't suppose any of those addatives like slick 50 would help? I am fairly sceptical about these wonder products

Thanks for all the replies.

Chris

 

[Mike (2)]

to be honest i wouldn't want to upset the semi-synth oil or the fuel chain at all.

mike

 

[AstraVanMan]

Cheers, was serviced about 1000 miles ago so should be nothing needed doing.

I don't suppose any of those addatives like slick 50 would help? I am fairly sceptical about these wonder products

Was it a basic service or interim service? If so (basically anything other than a major/20,000 mile service), then there's a chance the fuel filter wasn't replaced. What's the mileage on the car? Do you know when the fuel filter was last replaced? Maybe might be worth getting it done.

Regarding slick-50 and such like - a lot of people I know wouldn't touch it with a barge pole. There are websites dedicated to the technical ins and outs of exactly how it can potentially completely ruin your engine, but in short it's to do with the fact that the additives in stuff like Slick 50 which claim to prevent leaks are exactly the same additives that result in clogged oil pipes etc. At the end of the day oil companies spend billions in their research and getting their products exactly right, and any decent additives worth putting in their oils will be in there already.

Peter

 

[Clive]

We use the car on shortish journeys mostly and the driving is a bit stop start. At the moment wer're averaging around 18 mpg which aint good, and that's driving quite carefully. Does that sound about right? I did read somewhere before that if the lambda (sp??) sensor has gone that can cause bad mpg figures, is there any way to tell if it's faulty??

Cheers, Chris

is it a 3 litre? my omega only averages that and if its an auto and the air con compressor is on that will not help either

 

[Chris Peacock]

Was it a basic service or interim service? If so (basically anything other

than a major/20,000 mile service), then there's a chance the fuel filter wasn't replaced. What's the mileage on the car? Do you know when the fuel filter was last replaced? Maybe might be worth getting it done.

It was a 40K service but it had done 47K (not my fault, I've only recently got the car!). Think I will try a new fuel filter though, it's not going to cost alot.

Regarding slick-50 and such like - a lot of people I know wouldn't touch it with a barge pole. There are websites dedicated to the technical ins and outs of exactly how it can potentially completely ruin your engine, but in short it's to do with the fact that the additives in stuff like Slick 50 which claim to prevent leaks are exactly the same additives that result in clogged oil pipes etc. At the end of the day oil companies spend billions in their research and getting their products exactly right, and any decent additives worth putting in their oils will be in there already.

Peter

Cheers, that's what I thought, best stick to decent oil instead then

Thanks for all the comments, this is one of the best/most helpful newsgroups I've posted in

Chris

 

[AstraVanMan]

Was it a basic service or interim service? If so (basically anything other

It was a 40K service but it had done 47K (not my fault, I've only recently got the car!). Think I will try a new fuel filter though, it's not going to cost alot.

A fuel filter could well have been replaced as part of a 40k service (though a lot of main dealers are quite useless and would probably forget) - check the invoice for the service to see if it was replaced. If it has, don't bother getting your hands dirty. How long are the journeys the car's used for anyway? If they're all <1 mile then I'd say your economy is fairly standard.

Thanks for all the comments, this is one of the best/most helpful newsgroups I've posted in

Helpful? All of my comments are largely guesswork

Peter