Gs430 2001 - No Faults But 9Mpg Average

[dave1]

That's a thing. Nothing happening in a morning. Later on it starts to be laggy when it's a bit warmer. Problem is that I cannot make a video as I'm at work and then busy till it's dark, but I'll try to make some more soon. I've heard that problem might be oxy sensors not reset after changing though...

Pointless making videos and posting here if they won't play!!!

[TigerFish]

I've heard that problem might be oxy sensors not reset after changing though...

There isn't anything to reset after changing them. Replace, reset engine light, off you go. If any of the sensors are duff, I would expect a fault code and an engine light. Even when I had two knackered sensors on mine, the car felt no different.

[Zenekis]

Sorry I'll change it as soon as.... thought You could see it like this...

Edit: should be ok now.

[dave1]

VSC light seems to take a long time to go out. Looking at the OBC it doesn't appear to change either the 8.7 or the 9.0 figures. Has it been showing those figures all the time with just the top (current) figure changing? If that is the case then I would suspect that something on the OBC has stuck or become faulty.

I would brim fill the tank and check the mpg that way. My OBC has consistently agreed with brim fill figures since I got the car over 4 years ago.

[Zenekis]

It does change, maybe not constantly but it moved until it reached this figures and it stays like this now. As for other part actually it has been filled up the top and as You can see it did just over 100 miles on full tank. Nearly though but You know what I mean... ;-)

[TigerFish]

What kind of journeys are you doing in it on average? (i.e. distance and type of traffic)

[Ghosty]

Have a 2001 gs 430 with 50k mile avg 17 town 30ish motorway and goes like a bar out of help due to my obsession with changing fluids and stainless exhaust looking for a new home possibly. Looking for another jaguar or a gs 460

[Zenekis]

Just commuting 5 miles a day and sometimes about 15 miles to Sleaford or Newark but thats it. Once or twice East Midlands Airport which is about an hour drive. But when i drive about town for some time I've tried to be gentle and do not push to hard constantly looking at trip info.

You know when You feel like that there is something wrong when You feel car's urge to pull but he refuses to go and when it goes it does it in a struggling way. Like everybody says urban should be about 16mpg - I would accept even 13 knowing my foot but I am SURE something is wrong.

Here's video from a few minutes later that day when car was heated up. Maybe it will shed some light...

http://youtu.be/tNhkMJJXuTI

[noby76]

have it code read and checked over by your local Lexus dealer cus i wouldnt be able to live with 9 mpg on a car if its not an LFA.. they might charge to have the code read but you dont have to do any repairs and replacements with them rather just buy the parts from them and have local trusted garage who are familier with Lexus engines fit them.

[dave1]

Just commuting 5 miles a day and sometimes about 15 miles to Sleaford or Newark but thats it. Once or twice East Midlands Airport which is about an hour drive. But when i drive about town for some time I've tried to be gentle and do not push to hard constantly looking at trip info.

You know when You feel like that there is something wrong when You feel car's urge to pull but he refuses to go and when it goes it does it in a struggling way. Like everybody says urban should be about 16mpg - I would accept even 13 knowing my foot but I am SURE something is wrong.

Here's video from a few minutes later that day when car was heated up. Maybe it will shed some light...

I should try to get rid of it. Revs seem way too high for speed showing unless your right foot is flat to the floor, in which case it should accelerate far faster. A good 430 is a dream to drive but I suspect that yours was given a temporary bodge to enable it to be sold.

[ColinBarber]

hold the transmission in 2nd with 2,500 rpm and then floor the throttle, make sure the revs rise with the speed.

Has the exhaust been checked for any blockage e.g. cats broken up

[Zenekis]

Didn't check exhaust yet. Is it normal to have funny popping sound after You parked up, like from frying pan? Somebody said it's normal just cats cooling down...?

[Hondaman]

Strange that knowone has mentioned checking for a sticking brake caliper.

[TigerFish]

Strange that knowone has mentioned checking for a sticking brake caliper.

With such little journeys, even the urban figures would be difficult to achieve while the car is warming up. Ideally, would be handy if another gs430 owner was close enough to see it. I'm in Nottingham tomorrow and dont mind meeting near Nottingham somewhere after work, or I'm in Peterborough on Thursday and could meet around that area.

[Zenekis]

But this mean me going to Notts with 8,9 mpg ;-)))))) Which would be about 40 pounds in fuel..... And I am working 7am-5pm, then leave city stood in traffic means I would be there about 7pm. Tempting but I don't think it has any value at this point before I'll take it back to Lexus to have it code read. Sorry Rick, but after I've finished fixing it - with pleasure. Weird is that there is no problem at all on cold engine and then it shows up. I bet it would be some sensor somewhere...

[bobjol]

After a run, feel your two front wheels and see if they are very hot to touch. This model suffers from binding calipers and with the powerful engine, its not easy to detect when driving. A small amount of drag on the breaks can cause a lot of extra throttle pressure.

Not sure if this is your problem but its worth looking out for.

[Zenekis]

Car is in the garage at the moment - should know something tmrw. Then I'll check how the wheels spin when pulled up at my mates garage.

Ghosty - why are You looking fo a Jag - they are not very reliable at all...:-((( (I was thinking of getting XJ supercharged but lots of bad opinions around). And which one You're after?

Btw radiator is holding up as it was before, just need to top up some water every now and then. After I've managed to sort mpg out will try to lower it down and propably go LPG as I might loose my job soon. Then I should be ok to keep my Lexus costs down enough not to be forced to sell. We'll see.

[noby76]

since no faults have been found have you thought of running the car on higher octane fuel?? all high octane fuels include high concentrate of cleaning additives which cleans the whole engine system from the fuel tank to valves to injectors etc might be carbon/deposit build up over time from the previous owner which is robbing the engine from returning good if not better mpg! worth runing 2-3 tank fulls of high octane fuels then switch back to regular and see if mpg improves.

[Zenekis]

Right. Garage says after They've changed MAF sensor emissions are 50% better of what it was. Next ecu problem that was not shown before and now popped up is PO325 code. Waiting for quote and will commence repair as soon as salary comes through.

Edit: MAF sensor + garage fee = 180

Knock sensor 134 + 3 hours work to change it = 300

So I'll pay 480 to hopefully get it all fixed finally. Will see on friday the 12-th.

I was told that car will be ready on monday. Dam...n garages. It's week and a half already. Commuting wifes Mazda 323 ;-(

[Zenekis]

Got ib back finally. It was MAF sensor in a first place and then knock sensor underneath manifold. Costed me £480 and lots of patience testing... Still emissions are bit above to pass but I was told to drive it for a couple of weeks and we'll do test again.

Al least car behaves now like never before - response is way better than it was before.

See what will be after the trial.

[dave1]

Mine has around 64k on clock and just drove Coventry to nr Sutton-on-Sea, Lincs via M69/M1/A46/A152 at around speed limits but a couple of harder bursts. High was 32mpg but at destination it was 30.3mpg on my OBC which I know is accurate after 4.5 years of checking against brimfills.

[Zenekis]

Right. I have had enough with my Lexus. After changing knock sensor which aparently was next in line of all them faulty sensors(cost £480) there is another fault which is still causing high petrol usage - underperformance of catalitic converters. I am not even checking the price of them as I've heard they are ceramic and will cost dearly. Is is three of them as well? I have run out of money and haven't got nerves to try to get my car to run properly. It's just not what I was expecting to deal with after buying a car known to be very reliable. Sad, coz I love it and would like to be able to enjoy having it but it just is too much to deal with as I've lost a job too so fixing anymore is no option. Really when I think about what I thought about Lexus beforehand and now.......

[Lexmanic]

Have you actualy checked the MPG by filling the tank then drivng for a recorded number of miles, say 100, then refilling the tank & checking miles v liters. Dont rely on the display the aforeging is the best way to obtain a true MPG

[TigerFish]

Sounds like you have been very unlucky with this purchase. Sadly, the writing was on the wall for this car when it didn't even have the correct cooling system components. I'm surprised how hit and miss the diagnosis has been when fault codes should help.

[Zenekis]

Yes but some codes aparently didn't show up before other beforehand ones have been rectified. Then all ok and couple of weeks after another code pops out. Like i said before I went to Manchester from Lincoln A2 - then M62 and M60 doing quick ;-)))......Cause I could ;-)))))))))) and average was 15 mpg on motorway - to say straight I've used 3/4 of a tank while doing 235 miles. Thats £80 worth of petrol only to Manchester and back. That's well to much and then this knock sensor which was not popping out before and now cats. I love the car I would reaaallly like to keep it but how can I run a car with such mpg.