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16v Fuel economy probs

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There seems to be loads of topics about poor fuel economy with 16vs but I haven't came across any solutions to this problem. They didn't come out the factory with the sorted of economies being quoted and in fact several long term owners have noticed the figures getting worse with age.

 

Does anybody have a solution or recommend an order of check/replacement of likely faulty parts that may improve fuel economy?

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I was getting terrible mpg and I noticed one of the fuel injectors was so loose that you could near enough just lift it out of the engine.

 

Technically speaking though you'd know if that was the prob as she'd be chugging whilst sucking in the air.

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The problem is that fuel economy can be affected by almost everything so creating a list would probably include almost every part of the car....

 

But if your looking for a place to start i'd always go for the cheap easy options...Is the air filter getting slightly blocked? Are the spark plugs, leads, distributor in good condition? You could then move onto checking out the numerous sensors that around the engine.....Does the exhaust have any holes in it? is the timing correct? has the density of air changed in some way since the car coming out of the factory :wink:............the list could go on and on and on.

 

Of course it will get worse with age due to parts wearing out, sensors braking and not being replaced.

 

If you've got the budget for it change as much old for new stuff as you can...

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My car has had a recent service, and a whole new exhaust, and i still get around 22mpg in town. However, on journey's through the countryside i get a nice 32

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proper service with genuine spec parts and then a set up by a skilled person should see things ok

 

i see a shocking amount of garages that have no understanding of how j kets works and how to trouble shoot /tune/fix it

 

make sure the tyres are pumped up hard and the brakes dont bind( try pushing the car on flat ground)

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That's impressive. I think I'll start with a tune and take it from there.

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Anyone got any thoughts on these sort of things:

 

http://cgi.ebay.co.uk/FUEL-SAVER-FOR-VW ... dZViewItem

 

I keep seeing things like them all over the place. Sounds like sh*te to me - but I'm still learning. If it was that simple - wouldn't VW, Vauxhall, etc fit this kit themselves???

 

AVOID LIKE THE PLAGUE! They're a load of schitt. Magnets cannot improve fule efficiency. Even if they did do what they claimed (ie rearrange the molecules) as soon as the fuel had gone another few inches they would be back as normal, or be kerjiggered by the injectors. Pure cack.

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An older post I know, but I worked my mpg out the old-skool way (paper and pencil) and found that I got 37 mpg out of my last tank, although the computer says 27. Got this checked out at PSI when I got my cat done but Andy said that the computer seems fine (he checked the vacuum on it which is what it reads from I think). Either way, good to know that I am getting some decent mileage out of it, although it would be nice if the computer was accurate.

 

For any of you who are uber-lazy, then this site works out your mpg if you put in the numbers:

 

http://www.robinwhite.fsnet.co.uk/conv/ ... =Calculate

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I serviced mine and it's running much better. I'm still getting erratic fuel readings from the computer. One day it'll sit at 32 mpg and another 14. With it running so well I'm reluctant to spend the money changing sensors when there are other things like suspension and callipers that need attention. Nice link. :)

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I have found a solution to this problem, although its slightly expensive!

 

Since my engine rebuild im getting 30ish around town (which valvers dont like driving around) and 38-40ish on long journeys

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Are you also getting more miles per tank though? A slightly stupid question i know, i just don't trust the MAF......

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Does anyone know for sure how the MFA works out the mpg read out? Is it literally how many pounds of fuel against the milometer readout (from the gearbox i assume?)

 

Thats what i think it must base it on as i sit with mine running for 5-10 mins before i set off or leave work and used to get ridiculous mpg readouts like 12-15 mpg. Ive found if i reset it just before i moved off then its much closer to a real readout. I get on average 25mpg through city/town, 30mpg on fast back roads and motorways i usually get about 32-35 depending on what speed im sitting at and what gradient the roads are.

 

Ive never found it to be really really far off what i actually do to the gallon.

 

My brother has a valver and his is worse on fuel than mine, which i was very suprised to find out. I guess it all depends on how you drive em aswell but even if i thrash mine all the way to work i dont see anything below 19-20mpg. He seemed to think it was an exhaust problem on his as he'd had a decat pipe fitted and it seemed to coincide with that.

 

 

His car is on ebay if anyone wants a look.......

 

http://cgi.ebay.co.uk/1992-VOLKSWAGEN-C ... dZViewItem

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Its a bit different on a G60 as it calculates MPG figures from certain values in the ECU.. so, for example, when you fit a different pulley the economy figure will be incorrect.

 

I remeber my old tuned G60 used to tell me it was giving fantastic economy.. the pump of course told a different story.

 

I just worked out on that site that if i'm putting in approx 57 litres and getting about 350 miles out of a tank i'm hitting nearly 30MPG. Happy with that! My MFA tells me i'm getting nowhere near that! Mind you, in recent days i've been experimenting with very very light throttle usage, instead of normal type driving and its amazing how economical you can make these cars if you really just drive super slow. The problem is that in order to keep up with normal traffic, you just can't drive like in economical as you end up with reps driving about an inch from your bumper getting angry! Ho hum.

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I keep trying to drive economically too. It saves money, is better for the environment, and will make my car live a lot longer. But it's like my right foot is an itchy trigger-finger. BANG! If I had a gun things would get messy...

 

So I'll just have to settle for rinsing it everywhere, followed by a new engine at some point. And I'll keep recycling to lower my guilt per gallon :o

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