Trevor G

Thanks Paul, mines the 3.5L V6 so I have 2 'banks' of 3 cylinders but trying to find the 'pre and post cat sensors has been confusing. I've ended up ordering them all, even though the codes pointed at one, I'd rather not be off the road for 2 months waiting for parts! Cheers I'll share when it's fixed (fingers crossed)

Thanks Gamith, I've already got the codes P0037 HO2S Heater Control Circuit Low Bank 1 Sensor2 but before that I have had P0172 System too rich bank 1 and P0175 System too rich Bank 2. The sensor is there to do a job of sensing and if it senses something is wrong it tells the ECU. I've ordered all of the MAF, Oxygen and Air Fuel sensors as we have to rule out faulty sensors before we can rule out if there is a fault that is causing the sensors to do their job.... fun and games on a 16 year old 300,000km V6 Vellfire that still drives like powerful luxury ! Must be the sensors as it doesn't affect the driving!

Thanks for your response Terry, it's not getting the parts that are my worry (Megazip have been excellent), it's finding a garage/mechanic that is prepared to diagnose the problem. I could spend a grand on the sensors and it's something else. It's a cultural thing I think, people would rather say no than take the responsibility - not sure. I'm just lucky to be driving a V6 Vellfire around Thailand! :-)

Whilst my HiAce experience (petrol & diesel) is extensive (cough-they tend to live forever with minimal love), I am new to the V6 in the Vellfire. I’m currently with my (high mileage) Vellfire in Thailand and I have 2 questions: 1. I’m getting engine and (VSC) flashing lights on the dash and using the FIXD tool it’s determined that I have a faulty Oxygen Sensor heating circuit on Bank1 Sensor 2 and also getting System too Rich codes on both banks. It isn’t an ‘urgent’ issue, but I have had ithe issue for a few months (6500kms) and I have taken it to official Toyota garages in Pattaya, Rayong, Aranya Phratet, Sa Kaew, Muak Lek, Chonburi, (7) all of whom (as far as I can tell-my understanding of Thai is sh*t) have said – too difficult, can’t get the parts, don’t have the diagnostic tools. Toyota 1988 Korat have been excellent in fixing my aircon but again have ‘avoided’ the dash lights and codes ref the oxygen/fuel sensor issue. They have said it’s 45 days to get the parts from Toyota in Japan, and they can’t tell me which part. I’ve offered to buy all four sensors and the MAF (about US$900 up front) but still no joy… The van drives amazing, has no issues with pick up, or power or fuel consumption and I could probably ignore it, but the flashing VSC light (albeit orange) keeps making me think I’ve left my indicators on, so end up confusing the other road users whether I’m going left or right or straight on!

Hi I'm Trevor Short story long, I’m the very proud owner of two Toyota Vellfire GGH-20 2GRFE 3.5L V6’s, a 2010 in Thailand with 305,000k’s and a 2012 in Australia with 85,000k’s purchased in the last / 6-18 months after continuous and overlapping ownership of 4 Toyota HiAces with over 2,000,000kms between them across Oz, the UK and Thailand over the past 30ish years. I'm after some help, but will ask that elsewhere as per the rules!