Help, I'm baffled....

[-+Shadow+-]

I have a list, but I'll summarize it as much as I possibly can without trying to miss important details: I'll start with questions...

Q1: I'm staying at my g/f's parents place and was replacing my spark plugs & brakes... Her dads a know it all and pretty much pushed me aside from my own car when I was doing this, so I have to ask since I've never seen it... Should your spark plugs be screwed in tight enough that you're using a torque wrench to put them in? <--- Seriously Concerned...

The above mentioned question was about 4 days ago, since then, I don't know how these two could possibly be related but I'll give a few things that I think my help as well.. I work at Wal-Mart, thus, my pay rate is bringing pretty much from paycheck to paycheck without much room for excessive spending... but I hope you trust me in the fact that I have dreams for this mx3... as it's my second... and it's treated me better than most women I've dated... I digress..

In order:
Q2: Headed home from work, speed limit is 60, so around there... (I've been losing gas milage as well... I have a stock 4cyl...) Check engine light comes on. I stop at a gas station, and just to see if something was serious since I've never seen this... I cut the car off, disconnect the battery (not sure if this was a bad idea, but... I did it.. can't take it back now) plug it back up to reset the light, and it hasn't returned.... yet... upon finishing my journey (off the highway now), anytime I'm turning, as I shift in neutral, my car starts idling on it's own to approx. 2-2.5 rpm's on it's own... Which it does from time to time (on this journey).. Though of course, I'm testing and notice that it's almost guaranteed to happen if I press the brakes when I take a turn... I don't know how the engine light can correlate to the revving, but I figured if anyone could help, it would be someone on here.. And I'd rather ask you guys before I ask you know who...

Things I can tell you:
-It's been about 5k since my last oil change..
-Of course, the possible spark plug question...
-I've replace the fuel filter, but it's been awhile...
-There's an aftermarket intake on it... (with my lack of knowledge, let me clarify by saying... it's got a big a** open filter that hisses that I've been told is an air intake)
(I've never changed it in the 40k I've put on it...)
-New tires

I'm not good with terminology on cars, but I'm really trying to learn...

Final question that's not an issue...:
Q3: It's a 5 speed. Shifter rattles, kind of annoying... Rather loose. Am I missing something that holds it steady?

I know I made it longer than I should have, but I hope I didn't bore you... Thanks for any help in advance, I really do appreciate it, though again to be honest, I'm glad one way or another I remembered to ask you guys before I asked Mr. Expert... Since thus far, you all have never steered me wrong...

[crazycanadian]

Q1... Yes spark plugs have a torque spec.. I don't have it in front of me right now but its usually around 10 - 15lbs...

Q2 you need to start by figuring out what code is being set when your check engine light comes on.. Due to the loss of fuel millage if I had to guess with out looking at the car I would think possibly your O2 sensor is dieing...

[-+Shadow+-]

Q1... Yes spark plugs have a torque spec.. I don't have it in front of me right now but its usually around 10 - 15lbs...

Q2 you need to start by figuring out what code is being set when your check engine light comes on.. Due to the loss of fuel millage if I had to guess with out looking at the car I would think possibly your O2 sensor is dieing...

Following up on Q2, is there an easier way of figuring out the code then the old fashion replace everything you can think of? I thought the computer diagnostic scanner was only for cars 96'+?

[SuperK]

You can simply unplug the O2 sensor and see if your car's habits change.

Also there's a little diagnostics box under the hood, that you can take a paperclip and jump TEN and GRND. This will make the engine light flash and you can read the code. The codes will be properly displayed in a chilton/haynes as well as how to read them.

since you're in VA there isn't a code reader that you can use to plug in so gotta do it the old fasioned way. Check the FAQ's as well, there will be more detailed information on how to check your codes. CHECK. THE. FAQS.

for your loosey goosey shifter, there are bushings in the shift linkage that connects teh bottom portion of the shifter underneath the car, to the transmission. those bushings wear out over time and need to be replaced to "stiffen up" the shifter.

[93DrunkMx3r]

not much info on the troubleshooting...but glad to see another VA mx3r

[mazdaspeed23]

I personally wouldn't be following the specs on tightening the spark plugs, its really easy to snap those suckers. I usually put them tight then do maybe a quarter turn done. I would agree with crazycanadian. a bad 02 can cause bad gas millage, ive personally never had problems with idling with a bad 02 but I guess its possible