Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Thread cutting oil if available otherwise whatever lubricant is at hand will do . I should note I've never been impressed with the over the counter thread chasers and I normally end up welding new bungs in when they get buggered
