The gauge shows its running lean but it smells like its to rich when you idle it shuts off or it will go to 1000rpms then drop to 200rpms three or four times the it falls on its face and going down the road below 1800 rpms it sounds like it is misfiring but give it gas and it is fine . has lq4 in it but still has lq9 tune should it cause this or is it 02 sensor