Tammy

I'm sure reprogramming the PCM microcode resolved your problem.

Glad it's running normal ... Good Luck with it !

BLiu

First off, you are NOT stupid. You just were not as informed before going in. I assume you used the highest octane rating of gas. Otherwise, that's the first problem. The next issue would be the bad gas itself - one example, Costco is notorious for bad gas.

Second, there is no way to tune our GS ECU. Toyota holds all the keys to unlocking it and unless the shop is an authorized Toyota dealership, there is NO WAY they can retune the ECU. That's been the problem of why it's been so difficult to mod these cars. Right now there are only two solutions to bypass the ECU:

1) Get a piggyback module to steal the signals and "fool" the car.
2) Get a standalone AEM engine management system (EMS) and figure out each of the stock ECU signal points and mimic them with the EMS, which is ALMOST impossible.

Our ECU's as a whole control both the tranny as well as all the engine management issues. Neither is tunable by a third party shop.

I would recommend you stay on the problem. If you hear the pinging again, take it back to the shop and tell them they did not fix the problem since it should not come back after time. Also demand them to list exactly what they did. If you really want to make some noise, you can go back and tell them exactly what I said but tell them the Lexus dealership told you that piece of information. Tell them, you demand to know exactly what they did and that if they cheated you then it is the last time you will be coming to their shop and you will tell all your friends about how they cheated you and to avoid their shop. And then, at the very end, tell them that you are thinking about hiring a lawyer and taking them to small claims court because a Lexus mechanic has already agreed to go to court with you and testify. That should scare them a little. LOL!

Unfortunately, whatever they did, it was MOST DEFINITELY NOT a retuning of the ECU or reprogramming the ECU because they would be advertising for ECU tunes to enhance the performance because the entire Lexus community is dying for such a solution since once you can crack the code, you can do almost anything in terms of performance.

Good luck!

Brent

Och

iTrader: (3)

Well, actually what they told me when I was there, is that they determined that its a faulty PCM program. They told me they will take the PCM elsewhere to have it reprogrammed. It could be that they took it to the dealer.

But whatever the case may be, right now the problem is gone. I will stay on top of it and test it once a while to make sure it doesn't come back. If it doesn't come back, then even if they cheated me, the hell with it, im not gonna lose sleep over it. But if it does come back, I'm gonna gonna take it back to the shop and get to the bottom of it.

Och

iTrader: (3)

Oh yeah... I always use only the highest octane gas from reputable companies. Trying to stick mostly with hess, shell and sunoco.

DASHOCKER

iTrader: (2)

Hess is watered down gas. Get Mobil/Exxon if you can

LEXUSGS430

No offense but mobil/exxon are the reasons for high gas prices....they are thieves!

DASHOCKER

iTrader: (2)

Well they are stealing the good ish. My car runs smooth with Mobil

V8Lexus

heh...fascinating thread. keep this in mind, if the pinging comes back then all they did was disconnect your battery. also remember reprogramming the ecu to factory specs CAN fix the issue since over time since the ecu is a learning computer it could learn things that may affect it later. if they fixed your pinging issue they did 1 of 2 things. either reset it via disconnecting the battery cable, or they took it to lexus to have it reprogrammed. you'll know in a couple weeks which they did if the pinging comes back. also, whens the last time you changed out your plugs? that 100k mile stuff is BS. they say that so at 100k miles the plugs are so bad you end up frying a coil or two. i change my plugs once a year. its a small price to pay for peace of mind. anyway to that guy that said our ECUs cant be reprogrammed, thats also BS. anyone with skills and a laptop with the right software can do it if they know what they're doing. our ecu isnt so complicated that nobody can work on it. its that people are too lazy and or paranoid to actually disassemble it and modify it. its not like you plug it into a laptop and a screen goes BLOOP, please enter password,. some other things you should consider maintenance wise, clean out the throttle body, change the spark plugs, check out your air filter make sure its good n clean, have a shop do a fuel injection cleaning on it not just a bottle of injector cleaner. most common one is the 2 step involving CSF51 and CSF52, called Pro-Kleen. 1 is a bottle poured in the gas tank, the other is isolating the fuel and running the car for approx 15 minutes off 1 aerosol bottle of pure injector cleaner. really gets the gunk out of there. good luck with the pinging issue.

V8Lexus

och, also you're not stupid, in fact you're smart from what i read of all your posts. just because you cant fix a pinging issue yourself in an afternoon doesnt make you stupid at all. on our cars its quite difficult to diagnose an issue like that. you were smart to take it to the proper person to have it serviced rather than trying to fix it yourself and possibly making it worse. believe me ive been down that road. anyway, verify what kind of warranty you have on this "reprogramming the pcm" that they did. dont be skeptical if they wont tell you exactly what they did, some of this stuff is kinda like......."i know how to fix it but im not going to tell you what i did because im supposed to get paid to do it not give the information out for free", if shops just told us the steps they took to fix it then they wouldnt be around for very long because the information would become free. hence why diagnostics cost money. hey if i could knit my own shirts and jeans i wouldnt need to buy clothes, if i could find out why i was sick and prescribe myself the right medication i wouldnt need a doctor, etc. we're paying these guys for the training that they went through to be able to fix things that we cant. im also very curious if they gave you any kind of printouts as to their diagnosis. from my experience, a pinging issue unless 99% sure would take more than 1 hour to diagnose properly. when i work on a customers car and i put the car on the scope and scan tool and all of that i give them as much info on paper as possible as to what i did to ascertain the problem with their car that way they dont think im screwing them. let us know what you find out im sure we're all eager to hear it. thanks!

Och

iTrader: (3)

Hey, thanks a lot for the post. I will defenately keep an eye on this issue, and hopefully it doesn't come back. Right now the car has just under 80k, and otherwise than this pinging issue its running great. It didn't have a loss of power or rough idle or anything.

Reason I'm saying that I'm stupid, is because I didn't try resetting the ECU myself before I took it to the shop. It was kind of silly of me, because I'm not a complete idiot when it comes to cars, I worked on my cars before, and I was actually thinking about trying to reset the ECU before taking it to the shop, but then I decided not to, figuring that it would be better if they test it the way it is. But then, I doubt it was just a matter of resetting the ECU, because it wasn't some minor pinging, it was pinging mixed with loud *** cracks, that sounded like someone threw rocks into the engine bay. Plus its a fairly reputable shop that was recommended to me by a friend who has a hobby of re-building GM muscle cars (caprices, impalas) from junked cars and parts, and he uses that shop quite often and they are usually very good at detecting issues with his cars. So yeah, I want to believe they actually did have the ECU reprogrammed. How much would Lexus dealer charge to reprogram the ECU?

I know what you are saying about spark plugs, carbon build up, etc, and I agree with yout 100%, but I'm not really planning to keep the car for over 100K, in fact if my budget allows I will be trading it in for a SC430 with no more than 50k in the near future. I might do the spark plugs myself, because thats relatively easy, but throttle body and carbon cleaning is a pain in the ***. I also have a 94 LS400 with just over 100k on the clock, and it has a slight pinging issue at hard acceleration between 2600-3200 rpm, and over the past two weekends I removed and cleaned MAF and throttle body and did a complete tune up including plugs, wires, distrubutor caps and rotors, but the issue persisted. I'm thinking about running seafoam and cleaning PVC valve before I take it for diagnostics. I just bought the car a few month ago, it's in a pretty good condition, but previous owners apparently didn't maintain it much. The timing belt was replaced at 80k, so thats a relief, but spark plugs and wires were still original.

chuckb

I call BS on this. So you're saying you can reprogram a Lexus ecu? Can you change my timing and shift points to bump my 430 up to about 350hp then? You are the only one to ever know how to do this in the 6 years of CL history......right.

Och, I'm sorry you got ripped. they probably reset the ecu with an obd or just disconnected the battery. I would maybe demand more details from them.

V8Lexus

chuckb, 350hp isnt a realistic goal on our engines with just tuning, shift points isnt the ECU thats the TCU. i havent tried to get into one of those before.lexus did it all right from the start so theres not much improvement i can make without sacrificing streetability. you talk about it being a lexus(toyota) ecu as if its some impossible to solve rubik's cube. if you have the knowhow and the tools its not that difficult.

V8Lexus

think of it this way. what makes a lexus ecu different from the ecu in a twin turbo supra, porsche turbo, audi S4, honda S2000, acura nsx, etc. maybe a little software encoding and different style plugs on the back perhaps but its not as if its this black box of data that nobody can get into. its that the aftermarket isnt big enough to tune the ECU on a GS430 that someone would want to spend the $ to do the R&D on how to tune it.

JeffTsai

iTrader: (1)

Thats the main thing with the newer Lexus ECU's. Not just the GS, but all of the Lexus cars...the ECU code is encoded/encrypted. Then as you said, the market is not so big....nobody has cracked the ecu code yet. It's not so simple as to hook up a laptop and change the values of the ECU. Also, since the ECU is self learning on the newer Lexus cars...piggyback's will not work in the long term. Tuning is not the problem on our cars, but gettin the ecu to stick with those settings will be your main challenge.

V8Lexus

its not just newer lexus cars that have self learning ecu's cars have had those since the mid 90s when OBDII came out. you can get the ecu to hold those settings but the ecu code actually has to be changed. i.e. REFLASH. almost all ecu's that i know of have some sort of encryption, if there was enough demand for the GS tuning then someone would have cracked it by now. you hit the nail on the head jeff im glad someone here understands what im getting at.