Sweetdukes

Hi guys ive looked all over the search engines, other car forums and even Club Lexus forums to try and find an answer to this burning question I have in regards to my 2002 GS430.

I bought this car last week and filled up the tank 70 litres (18.492 Gallons) and of course drove it like a man possessed not taking any notice of the fuel consumption. However the next time I filled up the tank I cleared the odometer and actually wanted to know how many miles I'd be getting for a full tank. Now I will take into account I was using the air conditioning and did some mixed driving 60% Freeway 40% town...and I kid you not...my tank was on empty after 72 miles!?

Now maths is nowhere near my strong point but there is something definitely wrong with that level of fuel consumption...its almost 1 mile to 1 litre of fuel.

Now the mechanics over here in Lagos, Nigeria are bloody scam artists and will tell you just about anything to make you part with your money. So I wanted to ask any of our wonderful Club Lexus/GS members if they might know what is wrong with my car or if its completely normal? Ive read in the forums 18mpg, 16mpg even as low as 12mpg...I can only wish for those figures right now.

I'd like to have an idea of what I'm talking about if I head over to the mechanics and not be a clueless sheep that is about to get slaughtered.

Would greatly appreciate some input on this matter.

NorthStyle

iTrader: (16)

Well, if you're driving like a "man possessed": it's a V8 and will drink up while you're hammering the accelerator. But, most likely not to the extent you're seeing (1:1~ish)

However, if you're driving normally then no, it's not. As for what to check, there's a whole host of things that could be affecting your gas mileage: air filter, fuel filter, fuel pump, spark plugs, oil, alignment, etc. etc. etc. Hell, you could have a hole in your gas tank if what you're saying is correct. I'd even be more likely to believe that it's a whole range of issues simultaneously affecting it.

Is your car throwing a CEL? Do you have the prior service history of the car?

Sweetdukes

Thanx for the reply NorthStyle.

I drove like a mad man on the 1st day but drove like an average Joe once I had gottenspeed out of my system.

As for the service history...that kind of thing doesnt exist here in Nigeria...people will just tell you that it has been serviced and thats about it.

But I will mention some of the things you have listed ie air filter, fuel pump, spark plugs etc. The only lights that are on the dash that are lit up are the VSC Off & VSC lights. No CEL light though.

As for a hole in the gas tank...I dont see any gas dropping from the car when I have it parked either.

I appriciate the input

sam12345

iTrader: (1)

How many gallons/liters did you put in. Could be a bad gas gauge/sending unit

KeyKeeper

Bad gas is a good posibility. Did someone siphon your tank when you were not looking?

If the VSC lights are lit up, there is a problem with the car. They are pretty much a given with any sort of issue with these cars.

Sweetdukes

Its definitely not a bad gauge....everything was working fine.

I put in 70 litres (18.49 Gallons)

Got 72 miles for that full tank.

Sweetdukes

To my knowledge nobody siphoned off anything...however somebody tried to tell me that this gas milage I've gotten is normal ...I dont look that stupid do I?

As for t he VSC lights being on...im trouble shooting what I can...starting with the air filter & my god its was dirty as hell!!! Replacing that tomorrow.

DMPesso

Jesus Christ thats low MPG, probably lowest I have EVER heard. Things that will cause THIS LOW of MPG are bad gas, air filter, tire pressure, altenator/battery (since you have VSC lights might want to check that), O2 sensors (you would most likely have a code if these were bad), MAF sensor, spark plugs, sticking brake calipers or pads. When your driving and you take your foot off the pedal does the car coast well or does it slow down rather fast? Your getting roughly 4MPG which is HORRIBLE, even when I drive the car like I stole it and Idle 20 mins every day I wont get less then 8mpg and thats with idling alot, AC on and driving like a mad man.

KeyKeeper

Well if the air filter is stopped up, then that would explain it. I would pull the oil dipstick and smell it. It should NOT smell like gasoline....if it does...suspect bad injector.

1sWt2GS

iTrader: (6)

Obviously somethings wrong.. Do the Math if you put ~18 gallons into the car and you only got 72 miles thats ~4 miles per gallon.

Sweetdukes

I did the Math and thats why im here to find out WTF was wrong with my car.

newgsman

iTrader: (4)

Could be high pressure fuel line leak. Do you smell gas when you are driving. Check the fuel line and see if there is an area that looks wet or cleaner than the rest.

RichS11

Check your exhaust too. Mine is leaking air and that's affecting my mpg (not to your extreme though, but it could be a mix of things).

Sweetdukes

Actually yes I am smelling gas occasionally when I'm driving...didn't know what to make of it cos I had the windows down. Will take your advice & check the fuel line.

Sweetdukes

I know the exhaust was patced up as it did have a hole in it...but it isnt making any funny noises...so I think it might be fine.

Once again, I really appreciate all the help guys...you are making this so much easier than listening to some jackass who probably doesn't have a clue.