fuel consumption problem

[Stevie]

[Stevie]

fuel consumption problem

Proud owner of a '95 GS300 recently purchased from a Toyota dealership. Problem is, fuel consumption is only 15 mpg and I get a really strong smell of petrol when I start the car up from cold. It doesn't happen from warm.

I'm also getting huge clouds of water vapour coming from the exhaust, even when the engine is hot. Not sure if that's just the time of year, but it seems strange.

The engine also runs at 1500 to 1700 rpm from cold. Does that seems too fast? It settles down to normal when the engine is hot.

My Toyota dealer has checked the emissions and says that they are normal; so I assume I am wasting fuel on startup. They say I should go to a Lexus dealer to get it checked out?

Any ideas what the problem might be?

[Steve]

Hi Stevie and welcome to Team Lexus.

In regards to the vapour that is pretty normal.. i get the same with my 3 litre engine.. does it still emmit steam after a long run?

Also regarding your engine running at 1700 RPM on start up, thats normal too.. That is your automatic choke, mine runs higher when it is really cold.

not sure why you fuel consumption is so high... So do you have a computer that tells you your consumption?

Cheers

[Edited on 11-1-2002 by Administrator]

[Stevie]

Thanks for the response, Administrator, sir. (Sorry to be so formal but I don't see your name anywhere).

I haven't done any really long runs yet but the steam still comes out of the exhaust when the engine is hot. Coolant usage doesn't seem to be excessive, though.

I checked the fuel consumption the old fashioned way (3 separate times) topping up the tank and using basic arithmetic. I'm getting around 220 miles to a tank.

I guess the automatic choke must be supplying a very rich mixture, because the smell of petrol really is quite powerful when I start up from cold. Time to call the Lexus dealer I think.

By the way, this car really pisses all over the 5-Series I had a few years back. The paintwork gleams like a brand new car.

Stevie

[Steve]

coolant burning was an option i was going to mention.. but did not want to make you worried of something that is usally normal. I would definatly get it checked out through.. shoudnt really do it when hot... mine does sometimes though but mines an old 92.. so sometimes expected :)

Cheers

Steve

[blue wax]

mine's not steaming... untill now at least

[Richie]

Has the air filter been changed?

If it is very dirty the consumption will go up.

[Stevie]

The car was serviced before I took delivery, Richie. I'm sure they will have fitted a new air filter.

After a lot of to'ing and fro'ing, the car is now going to be collected on Wednesday by Lexus Chester to be sorted out.

Stevie

[Steve]

ask them if it is burning coolant... alot of mist usually means the car is burning coolant... though it is normal to have mist vapours on cold mornings whilst the car is warming up.

Just a thought :)

[Stevie]

>ask them if it is burning coolant

Thanks for the tip. I'll do that.

Stevie

[Stevie]

Well. I've got the car back and they tell me there's nothing wrong with it. Emmissions were low (which we already knew). The 15 mpg is because I do predominantly short runs and the smell of petrol when starting up is normal.

Great service. They called to pick up the car and left a loaner, and were extremely helpful on the phone. I could get used to that.

Do all GS300s stink of petrol in the morning, then?

Stevie

[Steve]

i guess it all depends on if the window is open and the exhaust fumes are rich... but mine does not smell inside of petrol.. even though mine is not a GS they are very similarish.

In fact mine reminds me of bakewell tarts.. the almond smell... quite nice smell but i dont get petrol smells.

let us know how you get on

[Stevie]

>i guess it all depends on if the window is open and the exhaust fumes are rich... but mine does not smell inside of petrol.. even though mine is not a GS they are very similarish.

I can't smell it with the windows closed. The smell is definitely coming from the exhaust and it's a smell of neat fuel.

>let us know how you get on

I'm now pretty much out of options. The Lexus workshop manager says it is normal. But he also said they have no way of measuring the exhaust emissions when the the engine is cold.

I'm half-tempted to reset the ECU but maybe I'm worrying too much.

Stevie

[Steve]

i get the same thing sometimes.. sometimes i listen to the engine and think it sounds rough.. when its not really.

i guess it pretty normal for the fumes to smell on start up.

What is the car like on long runs? Does the consumption improve? you should do about 25 - 28 MPG or even more on the motorway.

[Stevie]

>sometimes i listen to the engine and think it sounds rough..

Yeah, I know what you mean. You get used to the relative silence and small noises start to irritate you.

I seem to remember when I first got the car that I couldn't hear the engine idling. I can hear it clearly now and wish it were a bit quieter. From cold it sounds really noisy.

I'm a bit disappointed at the banging of the suspension when I go over a small pothole. The car was designed for smooth roads, I suspect. Reckon I'll do a spot of soundproofing come summer.

>i guess it pretty normal for the fumes to smell on start up.

I'll have to try and ignore it, then.

>What is the car like on long runs?

It definitely improves on long runs, but I don't have any figures yet. The tank was quarter full at 220 miles last time I did a long run. Normally it's at empty at 220.

I wasn't expecting great fuel consumption from an engine this size, and I don't do huge miles, but my 2 litre 5-series did 24 mpg around town. 15 mpg is pretty disappointing.

Still, there are compensations.

Stevie

[Steve]

I get abit more than 15 to the gallon around town.. though i do tend the glide the car... i use the gas pedal very lightly round town and it is so quiet i love it when it just moves and you cannot hear the engine.

In regards to the suspension.. yeah this is a drawback .. i need new suspension all round as i have a knocking noise when going over bumps... so i shall be replacing them... i get my bits from toyota... i can pick up a strut for £45 +vat new! which i think is pretty good!

I then goto my local mechanic as they fit them for half the price of Toyota... but then my import model has no history... like most imports there is no paperwork... kinda sucks though... so i dont mind if i dont get a Lexus/Toyota receipt...

[blue wax]

no way the smell is normal !!!!!!

yoou shouldn't smell anything at all.. certainly not a fuelsmell.. please check with another dealer if neccesary... you only want to burn rubber not your car..be careful

jacko

[Steve]

Blue wax

the car is not gonna smell of roses on start up.. it will smell a touch rich on start up... i diddnt mean it should smell like a petrol station on start up.

Stevie.. have you checked the plugs to see if they are rich? Usualy the plug ends can tell you alot.

[Rodders_UK]

My GS never smells of petrol.

I get a consistent 26mpg (according to the trip computer) and 99% of my mileage is high speed motorway driving.

I can't believe that a Lexus dealer thinks it's normal for such a quality car to stink of petrol!!

[Stevie]

>no way the smell is normal !!!!!!

Thanks. It's nice to have that confirmed. I've owned lots of cars and I've never known any of them to smell of petrol like this. It's not the smell of a rich mixture. I'm aware of what that smells like. This is unburned fuel coming out of the exhaust.

I talked on the phone to the mechanic who checked the car out. He said that what I was smelling was normal. I got the impression that he either didn't believe that I was smelling neat fuel, or that I was confusing it with the normal smell of an engine on choke. I specifically left the car overnight so that they could check it out from cold. No one I talked to said, yes, we started it up and you're right about the smell.

The service manager told me that they could not check the fuel mixture with the engine cold, but that if the mixture was wrong, the engine would run rough (!!). However, they had put the engine on the analyzer and the emissions were low. That's the gist of what I was told.

Before taking it to this dealership, I had talked to another one. I explained the problem and the service manager said, we'll give it a fuel consumption test, but if there's nothing wrong and the warranty doesn't cover it, we'll charge you a hundred pounds.

I wasn't very impressed with that. It was as if he hadn't listened to a word I'd said.

My diagnosis, for what it's worth, is that there is a problem with the choke. I've had two emissions tests and the offer of a fuel consumption test. Why can't anyone just fix the choke?

What do you guys think about resetting the ECU? Could that fix it, or could I just make matters worse?

Stevie

[Rodders_UK]

I think the first thing you should do is try another dealer - I've always been a little suspicous of Lexus service centres that "share" with Toyota - are you sure you're getting Lexus qualified technicians?

[Stevie]

The car was checked by a sole Lexus dealership. I can't knock the Toyota garage where I bought the car. I discovered this problem within a month of buying the car. They suggested that it would be better for a Lexus dealer to sort the problem out and they paid for the checkup. When they discover that there was no problem, it's going to make me look like a bit of an idiot.

I have 3 Lexus dealers all about 25 miles away. If it was a problem with the way the engine was running, I could just call in and say, hey, listen to the engine. But to observe this problem the engine needs to be cold. Which means leaving the car there all day.

Maybe, as you suggest, I'll call one of these up and see if I can get some kind of sensible response.

Stevie

[Shrek]

Stevie I am sorry to hear about the problems with your gs. I expect you would have had them sorted by now. I just want to add that my GS does not smell of fuel on start up. However it does sometimes sound noisy. I have not worked out the fuel consumption yet, as I am still enjoying its performance. I will do a check in the next few weeks and add my findings. If you have not sorted the probs yet I hope you do soon. :):)

[andyhart21]

I get abit more than 15 to the gallon around town.. though i do tend the glide the car... i use the gas pedal very lightly round town and it is so quiet i love it when it just moves and you cannot hear the engine.

In regards to the suspension.. yeah this is a drawback .. i need new suspension all round as i have a knocking noise when going over bumps... so i shall be replacing them... i get my bits from toyota... i can pick up a strut for £45 +vat new! which i think is pretty good!

I then goto my local mechanic as they fit them for half the price of Toyota... but then my import model has no history... like most imports there is no paperwork... kinda sucks though... so i dont mind if i dont get a Lexus/Toyota receipt...

I think you ought to replace your suspension with a new IS steve! Go on you know you are tempted:smilegrin:

[Stevie]

>I think you ought to replace your suspension with a new IS steve! Go on you know you are tempted

No, I love the GS300. Finest car I've ever owned. I'll get to the suspension problem once I've sorted the fuel consumption.

I finally got around to explaining the problem to Lexus UK. Nice people, sympathetic. I was impressed - even though the 'technical department' was non-commital about the problem.

I now know that I get nearly 30 to the gallon on long runs. I know that the emissions measure OK. I assume that the Lexus dealership found no problems with the central computer.

I'm waiting to hear, and I'll let you know.

Personally, and I have to admit that I'm not an expert, I think there's a problem with the fuel injection component that adjusts the mixture as the engine is warming up. Why else would there be such a strong petrol smell?

Maybe I'll post the problem on the American site, although I see that there are some engine tuning specialists online here. Surprised I haven't heard from them.

Stevie