Help, terrible fuel economy and maybe smoke from exhaust


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1999 White Legnum Type S Cold Spec with Recaros+Sunroof
I think i need some help. I was driving the car this arvo going up hill at 60 and it started to judder a bit. Stared it up tonight and it seems to be blowing some smoke:(( it could be that its cold outside). I've also got terrible fuel economy 130kms out of half a tank. I filled up on monday with the shell 100 octane fuel with ethanol. Is the petrol the trouble(hopefully) or has something gone really wrong. The car has been going well up to this point, 1800kms but the fuel economy has been getting worse only getting 350 out of a tank. What should i be checking??


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Cab Colt & Evo 6
First thing I'd do is a change the plugs, check 'em and make sure they ain't gummed up. Do a oil filter, air filter and fuel filter change. Get the O2 sensors checked. Have a carbon clean done on the injectors. Disconnect your battery and discharge the system (foot on the brake, used to work on my R32) then reconnect and start the car. That's all I can think of at the moment. Over to you Brad, any further suggestions


have you just changed to ethanol gas??

you know its not as effecient as normal 100% gas,
and you will use more,

also eth gas is a semi unknown on these cars, and manufactures on test on e5, and more and they say they dont know...

depending on what mix eth gas you using... this could be contributing to the problem. (degraded seals, EGO sensor, plugs)

also YOU HAVE TO change the fuel filter after using eth gas the first time as it picks up all the crap in the gas tank,

smoke... what colour??

eth gas obsorbs water... if theres been any in the tank, the eth gas will have picked it up in the first fill up. could be the smoke?? and shuddering,

you think your gas milage is bad mines.... 280km to a full 55L tank of 98octane (100% gas) around town driving only
or 450km on the open road only


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1 PFL & 1 FL Legnum
The smoke,- give is more info. If it was a cold night and the car was cold when you started it, its fine all cars do that when they first start....some more than others.
If it's blue smoke and it's constant then it's likely you've got a oil seal problem with one/both of the the turbo's.

Juderring, mine has done that a few times but only at slow speed. Can't help there

Fuel economy. What was is when you first started? A lot of people talk about how much fuel they get out of a tank, a better measure is how many km's you get from a litre. To work that out next time you fill up, reset the trip meter. When you fill up next divide km's by the litres you added, this will give you km's per litre. I get around 9-9.8. The car doesn't do a lot of stop start driving.
The small turbo's coming on boost very easily, its pretty easy to get crap fuel economy, if the car has a boost gauge fitted, try using that and accelerate with out coming on boost (not as much fun ) and see how that effects your economy.

Also as Peter D said, change your plugs, mine were _ucked, the car is soooo much nicer to drive and fuel economy had improved slightly
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