ColinBarber

Have you had your coolant changed recently? Air in the system can cause this, an air bubble around the sensor will make it read cool. Do you have enough coolant in the system?

By updated do you mean new map data? You can purchase new maps from Lexus but it is expensive. http://www.lexus-mapupdates.eu

If you register without the id and then use that username and password to connect it should register itself. Are you sure the Internet connection itself is working? Are you using bluetooth or wifi?

how bad is the service history? The engines are quite reliable, especially a 2009 one. Worth noting if there is any knocking/rattling on startup which could indicate a problem with the timing chain and sprockets.

The MAP sensor has a vacuum tube going to it, if you remove the tube you need to block it (the pipe) otherwise you have an air leak. http://www.autoparts007.com/oem_89421-20190/Detail_3093_Pressure-Sensor.html

Used NX prices seems to be extremely high. Lexus are doing a good job at holding this although I fear prices will fall rapidly once 3 year old vehicles are available on the market outside of the main dealer network. Lexus dealers will typically offer a trade-in some £5k below retail value on the NX at the moment.

You need to make sure you don't have any air leaks, e.g. a disconnected or split pipe. If you removed the map sensor did you block the vacuum pipe going to it? Potentially if the ECU is in limp mode it won't use the sensor reading anyway. The TPS errors will need to be cleared first. This is a mechanical device, the map sensor won't affect the TPS errors. Either the TPS sensor isn't adjusted/working correctly or the throttle motor isn't working correctly.

Please keep this thread on-topic. If you want to discuss wheels please start a new topic.

Brake callipers (sliding pins) might be seized, take it for a run and check the temperatures of the wheels to see if one or more is very hot. Check for creaks and body roll when cornering, some of the suspension rubbers might be worn with age. Otherwise just check the standard things and make sure the warning lights come on and go out with the ignition, if they never come on the bulbs might have been taken out to hide an issue.

I had mine for around 5 years and it had 110,000 miles on the clock when I sold it. No issues other than the 12v battery was getting a bit weak so I swapped it out in the last year, re-lubed the brake sliding pins a couple of times, replaced the rear brake discs due to corrosion, a set of brake pads all around, and had to re-glue the seal on the rear of the rear light clusters as I started to get water entering the boot on one side. Other than that just routine services and the inverter recall.

I think it's on the kick panel, to the right of the accelerator pedal.

Yes it is in the drivers side fuse box. Labelled CIG, 15 A - it powers both sockets. If you remove the cover there is a diagram on the back.

when you consider how few GSs are sold the issues aren't that rare. We have a lot, lot more reports of GS hybrid issues on these forums compared to the similar aged RX400h, yet that outsold the GS450h around 6 to 1.

Did you try a series III or series IV RX450h? The series III interior looks quite dated now, the NX and new RX are big improvements, as is the exterior styling. You will miss the performance of the 400h with the NX.

Probably best to get a mechanic to look at it. The sensor should be checked for alignment and possibly replaced if it isn't working correctly. The throttle motor should also be checked for correct operation.

Both codes are related to the throttle position sensor. m_di_0042.pdf

Yes I guess that must be correct. Not sure why it is listed like that. Denso do their OEM sensors which are much cheaper than the Toyota stamped ones. Import from the US, for example from rockauto.com

although GS300 is much more reliable. Most Toyota/Lexus hybrids are very reliable, the exception is the series II GS450 - battery and transmissions problems which can be fixed relatively cheaply if you are mechanically minded. If you go to a main dealer it could cost you thousands. Looks through these forums.

Congrats and welcome

although a minor issue I'm sure it will cost a major amount of money to replace.

which one? http://www.toyodiy.com/parts/p_E_2002_LEXUS_IS200%7E300_JCE10R-AEAVFW_8401.9.html?hl=89465

Only Bank 1 Sensor 1 and Bank 2 Sensor 1 could have an affect on the engine, the downstream sensors just monitor how well the cats are working and produce an error if necessary. If both cats are getting hot then it sounds like the engine is running lean. If it was just one cat then it could be blocked but I cannot see two cats getting blocked at the same time. Also the fact the both cats are excessively hot kind of rules out that an O2 sensor is at fault because each upstream sensor controls just one bank of the engine, you would expect only one cat to get hot. You are therefore looking for something common across both banks, such as fueling, ignition and air control. If this issue is with both petrol and lpg then you can also rule out fueling therefore an air leak, faulty MAF sensor, ignition or poor electrics are likely causes.

Yes, the same systems have been used on Lexus vehicles as well - the odd RX400h has been converted. In theory it should be possible on the IS, but their battery packs are designed to be installed in the Prius and therefore may not fit correctly. This system doesn't modify the existing hybrid system, it just presents a fully changed battery to the system so it can run on EV longer. It doesn't improve the maximum speed that EV works at etc. etc. http://www.enginer.us

What does he mean by second O2 sensor? Bank 1 Sensor 1, Bank 1 Sensor 2, Bank 2 Sensor 1 or Bank 2 Sensor 2. There are 4 O2 sensors in total.

Provided it is the correct disc for your system then yes that will work and allow operation when moving. This is an original disc, not a fake, and therefore will contain the firmware update required. The reason why it is cheap is because people purchase a new disc set from Lexus and then split the set, selling the individual discs separately - most people only want the single disc that is relevant for their country.