Female Mazda6 owner who might have messed up Engine =0(

so… I need some opinions here. apparently, i left my car without oil or little oil and now my car sounds like a diesel truck instead of V6. Now prior to that fiance did tune up but never replaced my coils. car started to shake as if it was turning off, so 2 coils ended up misfiring and they were replaced. a week went buy and car started doing it again but was starting to shut off while in idle. Fiance went a head and changed all the coils and found out that the 3 spark plugs underneath the manifold where loose that he was able to take unscrew with his hands. so he checks the oil and finds out that i have very little oil left in the car. so he puts oil in and is reving my engine and white smoke is coming out of my exhaust. so now the car is sitting at home… when its been siting cold and i start it up the RPM’s jump from 0 to 3 then immediately drops down below 1 like its going to shut off and does this maybe 2 more times and stays at 1 all while still in park but doesnt do it when its in park. Still has a really bad knocking sound.



SPUN BEARING OR NEW ENGINE??

You could be really lucky and have minor issues that can be repaired at a minor price. You need to have a proper engine analysis done, that unfortunately cannot be done online to thoroughly asses your situation. (ps female makes no difference!)

It sounds like you may have several problems, the worst of which is the knock. You were both not too bright for neglecting to check the oil until it was almost bone dry. I think you’ve done severe damage to the engine and it will likely need to be rebuilt or replaced. If he changed the plugs, he must not have tightened them properly if they were that loose. Ignition coils are not normally replaced as part of a tune up unless they are weak or failing.

I don’t know about the white smoke (steam?)–you may have a bad head gasket too, or it could be accumulated unburnt gasoline that was coming out as vapor due to the engine misfiring. The RPM issue could be a bad engine sensor or related to the computer trying to control the engine while one or more cylinders are misfiring.

At this point, I think you should take it to a pro (not necessarily a dealer) for analysis, as it seems that neither of you are that mechanically inclined.

I had to repalce the engine on my 2004 V6 Mazda6 with only 81k on it. It had no previous issues (other than bad coils twice), was extremely well maintained, and had not gone low on oil until it basically blew up and shot about a quart and a half of oil into the front cats. Long and short, got a reman engine and replaced both front cats. Avoid the dealer, you shoudl be able to save at least $1000 with an independent on this one.