Hi, I bought a 2002 GS430 SE Auto 2 months ago, an LPG Romano conversion, but the next day the engine management lights came on, so I took it to an LPG diagnostic, and he said that the error is P1651 and he mentioned something about VSV. So he sent me to a Lexus dealer because he couldn't get rid of the light. Lexus said that the oxygen sensors and VSV valve are required, and the specialists told me to return the car to the dealer, so I did that. They said they changed some stuff, I don't know what because I am still waiting for the invoice. So I picked it up last week and no lights were on and they said it was fixed. It was fine for 50 miles, but then the EML light came on and 2 days later the VSC lights came on as well. I noticed that when I picked it up, the heating wasn't working and it hasn't worked properly since. The acceleration is quite good, but once the engine almost cut out, so I took it back again and they told me that on petrol it works fine, and no lights were on but when they switch to gas, the lights come on. So they advised me to go to an LPG specialist. Could someone please tell me what the problem might be?
Thanks in advance.
