There doesn't have to be any residue in a smoking device to be charged or convicted for 11364 Health and Safety Code. The statute specifies that it is illegal to possess any device used for unlawfully injecting or smoking a controlled substance. I don't know what you mean by an oil burner.
11364 does not require residue, but when it does the DA uses that to prove it was a meth pipe. If the pipe is clean it can be argued that the pipe has a legit purpose such as smoking tobacco.
I am also unfamiliar with this oil burner concept. If the device used to smoke the meth is not a traditional drug smoking device - then I would guess the police and DA are trying to say this oil burner is a meth pipe.
Regardless you need a lawyer. Ask for a public defender if you cannot afford one.
The above information does not establish an attorney client relationship nor is it meant to provide legal advice.
The statute for possession of an illegal smoking device (Health and Safety Code section 11364) does not require a device to have any residue. I am not sure what you mean by an oil burnner, but if this is the device that has been used and it can also used for some other purposes, e.g. to burn oil, then if there was no meth residue on this device, your attorney can argue that the oil burnner was used for legal purposes. It all depends on the facts of your case. It is difficult to answer your question without having facts of the case. If you are charged with violation of Health and Safety Code section 11364, then you either need to ask a court to appoint a criminal defense attorney for your defense if you cannot afford one or you should hire a criminal defense attorney if you can afford it.