Kaminet

I'm pretty sure, that in his case, if the MPG is so badly hurt, he also experiences loss of power and what have you... Due to compromised chamber sealing I bet that his injectors aren't operating at optimum... And quite possibly his exhaust valves aren't the cleanest either, some raise in operating temps can only benefit, to an extent. As one of my co-workers likes to say: "s*** only rolls downhill".

I didn't say a thing to state it will clean valves... It's not a port injected engine. Keeping the rest of the system clean were my actual words. And I said the rest of it, because it's a 2 shot bottle, which is twice the required/recommended amount, combined with catalytic converter detergent and octane booster. Which in return means that if you drive long enough to get everything up to temperature whatever buildup you have past intake valves that can be cleaned chemically or thru burning it will be cleaned. It's not cheap either, for what it is, but it does seem to work.

The chap on Ebay is located in Hinckley. Fair distance from London, but in all fairness I would do the trip (spits behind shoulder), if I(hope I'm not calling the devil) have to. The procedure is about 4 hours, his own words, and all including travel can be done in a single day. There's a link to his profile https://ebay.co.uk/usr/pmp_cars Googled around to see if he has any sort of credibility, and his reputation seems pretty good. The catch can itself is no cure, but it does make a difference in the long run. Needs draining every once in while, nothing major as maintenance required. I, for one, am not only sceptical but pretty convinced as well, that the seafoam can do a lot of harm, and will definitely not clean as much as you would like it to. On the other hand, £400 is not something you can easily swallow... The decision is yours. Best of luck!

I've done some reading for you, and I doubt your issue is a bad caliper. If the engine isn't throwing a specific code you're one of the "luckiest" chaps to get excessive carbon buildup on intake valves. Save your time, and money, and do it right the first time... On Ebay there's a "chap" who is specializing in cleaning direct injected engines. And I've messaged him, with a price request for is250, he came back with £400 and done within a day for walnut blasting. Which is the only right way of cleaning the valves in the long run. After, or before that, you may consider installing an oil catch can, fairly simple procedure, to minimize such occurrences. My two cents in this is, on your next few refills use some injector cleaners, I do it in combination with octane booster and cat detergent, it's a bit expensive considering the price of petrol, and then adding another 25~30 quid into the tank, but it is means to an end... And although this does nothing to prevent or remedy the buildup, it keeps the rest of the system clean, and helps with mpg. Don't have to do it all the time... Refill to full once and pour a "two shot bottle" of RedEx (don't worry will do no harm), skip next one, do it again on the third full tank, and that should do for a while. But definitely have your valves inspected/cleaned.

It may seem strange, but find an excuse, take the car on the motorway, preferably in a section without speed cameras and floor it... Amongst other things, tha cats need sneezing off every once in a while... really fussy those cars we're driving turn out to be... Need tickling all the time.

Last night when I parked the car the fuel light came on, it didn't this morning... But nevertheless there it is... Overall mileage and miles since "improvements to fuel managing applied". I must say - I didn't expect that to happen, at all.

Last time I spoke about mpg, the topic got locked... For whatever reason... So there it is: Ion a recent cross Europe trip 75mph for about 300miles I've got 46 tank mpg from Netherlands to Calais, which ended at 45.0 in London. As you cant really speed in those countries where police is taking radar and laser readings of speed, I decided to play a game of "see just how much of an economy I can get out my 07 is250", and that was the result. It'shard work though, and not really worth it... I haven't yet filled up in uk, but London traffic has taken it's toll and that particular tank is currently reading 41.8 mpg. Just got the light on. A while back (about two months I think now) I remaped the vehicle, i know... i know... and from 26.5mpg my overall mpg is 34.6 as I'm writing this. Haven't reset the trip B odometer reading since I've mapped it, just to take a considerable amount of distance into account. In Germany my fuel economy is bad even on the motorway, averaging at 28.5... good fun though. While everywhere else is above factory figures. I'll take a picture of the "all time" mpg later on today. You can get some sort of economy out of this engine, but you will most likely lose all the fun.

You're misinterpreting what I'm saying. It's not what you are saying, it's the way you're saying it... And if you want to see what the results are PM me, and if not too much bother we can meet over a.drink and you can test drive the car for yourself. No threats here... the way see it, it's a fair warning. You've been talking to me "in a manner" and I've tolerated it long enough. I'm not pushing anything... sharing my observations is what I am doing. That's all.

Lines.P again, I'm not arguing benefits, pros and cons... I'm sharing my own personal experience from the doing of such a thing. And honestly, you don't know me very well... but I'm not a believer in fairy tales and pixie dust stories. I'm not only mechanically inclined but also can find my way around a spanner set... Never been bothered to register on the forum, for a simple reason... Didnt needed much info as to how and what. But have been reading it for years... Not my first Lexus either, and only in the past 3 years I've done more than a 100k miles inside one. Maintained and repaired twice for the duration of my ownership exclusively by me. I know the difference between crank hp and wheel hp, and what an ECU tune can do to a turbo/supercharged car... decided to catch the wild goose and see if it can do anything to a NA engine... And, no, not really, I'm not saving fuel, and I'm not claiming anything at all... Just my case, the car meets the official figures, so far...Sharing my experience so that people aren't discouraged that it is impossible and nothing can be done... isn't that the whole point of a forum? Even though I've driven it a fair mileage, it hasn't been too long since that had been done, so if anything changes, or it is consistent over a prolonged period of time - I will update my post. The exhaust system is undergoing an upgrade during this summer, along side, potentially, a better fuel system... Still researching on that topic, as to whether is it worth it or not. And then will be mapped again, this time around properly... although I doubt that a rolling road session will change anything dramatically on a non-turbo engine. Oh, and by the way... enough if that "cold air intake" on a NA car... You did mentioned a few time that you know a thing or two about cars... please... Pretty please, the only thing that makes any difference whatsoever is the amount of air. Can't claim cold air intake, if nothing is cooling the air that goes inside the engine... Right? "Cold air intake" on a NA engine should be Insulation around the air piping and the filter box, so it can not be heated by the engine, simply replacing a pipe does f*ck all as to keep the air cooler and it had been proven to be a waste of time and money a million times over by a million independent people. The only thing that could and it is making a difference is the 360° air filters allowing slightly higher airflow. But again, the pipe they're attached to it is not doing anything but holding them, and potentially limiting the pros of having them fitted in the first place, by simply getting hotter faster and to higher temps than the factory rubberised, nylon (insulation, remember?) air intake.

And... you're supposedly the only one "knowing thing or 2 about cars"?! If you pay the dyno, I'll put the car on it. You have a stock spreadsheet figures all over the internet, compare to that. Btw I haven't stated any figures whatsoever... apart from a better 0-60 time. Just saying... Has it ever occurred to you that apart from your opinion there might actually be something else? And again - I'm not trying to change anyones mind, or convince anybody of doing it, as I can't guarantee same results/level of satisfaction... I wouldn't recommend anybody for the job, and I'm most definitely not trying to advertise anything. I know I was taking a risk, with potentially nothing to gain, and also potentially a fair bit to loose... For me, my gambling, has paid off... For someone else that could be a new ECU... or all sorts of issues... I don't know... Could be nothing at all, either way...

Well, thank you, for acknowledging the fact that they're a bit too happy to say it won't work... This topic has been going for a while, and as far as I can tell - I am the first to actually try it... So, there it is... And I only posted, as to clarify that a remap on is250 is possible, I know at least one man that can do it, and I trusted his abilities enough to put my own car in his hands. IS250 is an NA engine, so the best you could hope as rough numbers in performance are 10% across the board. Period. Whether we like it or not this is it. The difference the remap does to the car comes in an improvement of how the power is delivered and then distributed. Dynoing before and after... who's paying for all that?! Just to prove that there's, respectfully there isn't change in performance?! I'm of the type of people for whom the proof is in the pudding... I know someone that remaps vehicles, and his reputation is bulletproof as far as I'm concerned. I've seen people travelling from Belgium, Germany and France going to him to get their cars evaluated and tuned (he's Honda specialist). If he can't do it, or it isn't worth it, he won't do it. He declined me at first... but then he found a way of bypassing the Denso ECU encryption and as you can see on the pic above - my ECU is out of the car, and onto my kitchen table, yep he came to mine, and I've been an eyewitness of the whole thing. Wouldn't have trusted probably anyone else with this, if I have to be honest. But he has done a good job, and so far I can only tap myself on the back for doing it, knowing that this could make absolutely no difference whatsoever, or can mess up the car completely... Long story short: Is it possible to remap an IS250? Yes it is. And as far as I'm concerned it's well worth it. Everyone has to make that decision for himself. Peace out.

Not being funny, but you won't get nothing nowhere near that after an Amazon Flex route... Comparing apples to oranges... Not for nothing I mentioned it... Just how stubborn ya'll got to be to try and convince me, after trying to be as realistic as possible about the whole thing, that my car does feel and sound different than before?! Not bragging, not saying it's economically justified, or does something that improves an already fairly above the mark good all rounded vehicle, not even saying it is worth it for the aforementioned reasons... It does do something, and whatever it is, it makes the car feel a lot, and I mean a lot, better than before. (Especially if you disable the electronic nannies and try to have a bit of fun) Average tank is atm 35.9 MPG... You'll have to take my word for it...

And just to add to the confusion, 2000 miles after that and not entirely conservative ( 😜)driving, daily commute of about 110miles, plus Amazon Flex my combined mpg all round is approaching the unattainable factory figures. So you tell me of whether it is worth it, or not...

You do realise I'm talking about my car, right? I've driven it before... I'm driving it after... And to my surprise I can still notice difference in both noise and behaviour... Whatever the changes the map has done, they are there. The "throaty" exhaust comes from the combination of both less restrictive air filter and remap. There are mechanical parts to the exhaust system and the dvvt-I system is reprogrammable... which in turn leads to change in behaviour. And yes you're correct... to an extent, the factory unit isn't OBD reprogrammable... it had to undergo surgery.