dcevnu

If your fuel system is stock standard and no aftermarket parts have been put in, then the fuel is not a cause of the problem. It is your "idle air control valve" that is playing up. It's dirty and needs cleaning or replacing. Try to avoid going to wreckers to find the part, get contact to a Lexus dealer or Toyota dealer (jdm models), cos the used ones will eventually catch up to u soon. Also, check for any pinched hoses that are running off the bypass valve that restricts flow.