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Recently, the Polo has been experiencing TERRIBLE fuel economy, Im talking..70 miles to £10 at 50p/ltr so duno what that is but its bad.
Ive tried driving less harsh with it and still, bad.

My only thought is: leak in exhaust between back box and..other.long..bit..of pipey thing?

If not? Clean carb? bad filter? jets??
Vaccum hoses or something?

What else can it be? Please help?

Justin

oh and PS:

Thx for replies 2 previous comment I made, i never got round to writing back...I've got new headlight bulbs and they work a damn treat!!

15.9mpg - that's seriously bad for a mk2

You ought to get the exhaust fixed, but that won't be the source of quite that bad a problem. Any chance of some details on the car? Year and engine size would help.

First port of call is to check the spark plugs. If they're very black and smell slightly of petrol as I suspect they will, you're overfuelling, which could be due to a faulty automatic choke (or a stuck manual choke), poorly adjusted carburettor or blocked air filter to name a few things. If it's not the fuelling, try the ignition system - check the ignition timing, the spark plugs, leads, coil, distributor, distributor cap, rotor arm. When my car was drinking petrol I tried everything, until I had to replace the dizzy as it was rattling, then it jumped up about 5 mpg.. does have a big effect overall.

Another thing to check is that there's no physical resistance - brakes binding, underinflated tyres, worn wheel bearings etc.

When was the last time the car had a full service? Oil change? Gearbox oil topped up? Does the car feel like it's driving normally or is it a bit sluggish?

Hope some of that helps.. let us know a few more details and it may help a bit.

Hi..its 1L.. 1990 with weber carb..60K miles..

I will give the spark plugs a check tmoz and see whether they're smelly or wet..the automatic choke appears to work..maybe..because theres the lack of power when starting and then you wait until the engines hot and its responsive as ever.

I'd say the car was more responsive than usual really as now..(not often and not recently) the car has comfortably been able to reach 96+mph but I mean the reason I guess exhaust as its been since the leak started so? Im just wondering whether it could make that much of a difference.

Ta

Again..PS!:

Not sure really how to repair the exhaust, I've put the special glue stuff between the joint, still wont stop it, and also got new clamps..what more can be done?

Use gun gum - it's an almost solid paste, fills anything, good stuff. If the leak is at a joint then make sure the pipes are fitted together correctly and clamped tight enough, if that doesn't work then resort to gun gum. Still, I don't think even a pretty severe exhaust leak would put you down to 16mpg.

Btw, the car shouldn't really be noticably low on power when it's cold, usually if it is it's a sign of underchoking rather than overchoking. It won't be race worthy on choke, but unless you're thrashing it you really shouldn't notice.

Depending on the overall condition of the exhaust it could be wise to buy a new one. A local garage does downpipes for £40 inc. fitting (That's for a Ford Orion but I shouldn't imagine it would be that much more)

Check the brakes, my G/F's 106 had siezed pistons and that not only made the car slower, but did drain petrol noticeably. All I had to do, (I don't know if it's the same for a MKII Polo) was take the wheels off, take off the calipers and lube the pistons. The 106's brakes were pretty stiff and I was surprised how much a squirt of WD40 did!

You seem to be losing hardcore amounts of Petrol so I reckon it's a more complex problem but hey I tried to help

You could of course have a fuel leak somewhere! The filler neck to tank join is a common place to leak from.

Right, I've taken it out today again to try and put it in perspective for myself, despite a go at the engine in the rain..spark plugs burning fine..dont smell of un-burnt fuel..doesnt appear/smell to be a fuel leak anywhere, it would be obvious surely.
The exhaust is in perfect condition and is practically brand new, it just WONT stop leaking from the joint bit!

Anyway yes, to put it in perspective..i went out with the fuel on the last little white mark and went about 15/20 miles at a steady 30/45mph at low revs, foot barely on the throttle and now its half way down between the last little white line on the fuel gage and basicly touching the red.

Ideas?

Are you sure its that bad? If your getting petrol for 50p a litre then you will have to share the secretl but if you are paying normal prices then it looks around 28 mpg. Polo fuel guages are a bit inaccurate anyway, only way to be sure is to brim it full, do a good few miles (at least 100) and then brim it again (also a good way to check if your filler neck is up to scratch!). That will let you know what you are actually using, rather than what the guage says.

Even if you are really ragging the car you should still be getting 35-40 mpg.

turns out the mrs' car was a bit messed up...

We bandaged up the exhaust, and sorted the brakes, it's still making a racket. The front wheel bearings need replacing... this car is a nightmare!