I've been coming to this site for awhile, first time posting. Please warn me if I posted this in the wrong place!

I have been the proud owner of a 2008 Cobalt SS/TC for about a year and two months now. I bought it with 42k on it and have now just rolled over 53k. My question is this: Other than regular oil changes with a reputable full synthetic and good filter (I know there's better stuff than Mobil 1, but it's easy to find and the filters are good, so that's what I use), what else should I be looking into doing as far as my around 50k maintenance? I have read the user manual and it looks like the usual stupid proof "take it to a dealer and leave it alone" crap for the average user. "Never touch the transmission fluid?" umm....really? Is there any truth to that? Stuff like that is why I'm coming to you guys for help.

I'm not new to working on or owning car or trucks, I've owned lots of different vehicles and, free time permitting, do most of my own work. From a 98 Ford Escort Zx2, 01 Mustang GT with lots of mods, to a lifted Jeep Cherokee that I used for off roading and a Tahoe towing rig with 200k on it. Only difference is that this Cobalt is forced induction, and that's uncharted territory for me!

Now, as far as my driving habits, I don't beat the **** out of my cars. Well, at least not constantly. It took me eight months of owning the Cobalt to work up the courage to try out the launch control and no lift shift because it just sounded like a one way ticket to a new clutch . Usually I just drive the car to have a little fun, but it is still my DD and needs to get me to work in the morning. Sure, I will take up an offer to show someone up at a red light, but those times are few and far between.

Now, onto the problems I have had (they aren't very big, but more of an annoyance):
I bought the car in April of 2012. Around October of 2012 (when it started getting chilly) My car started slightly misfiring on cold start. Not a bad misfire, just a little bit. But apparently enough to set off a CEL for misfire on cylinder #1. The car runs perfectly fine after it warms up. I read it was probably carbon buildup, spark plugs or the coils. I seafoamed it through the vacuum hose, changed the plugs and switched the coils around. Guess what....it keeps coming back. Of course. Anyway, I've just lived with it since then. It goes away sometimes if I drive on a long trip (I drive from Lincoln, NE to Detroit, MI and to KCMO once in a while for family and friends stuff).

The Second Problem is my e brake is really loose. Like, if I were on a slight incline, it would not hold my car. I know it needs to be tightened, but that is one thing I've never done before. Is it easy to do on your own?

Third problem has been within the last month. My "Service Air Bag System" message appears and the passenger airbag doesn't turn on. It also only happens when a passenger is sitting in the seat. I'm thinking something to do with the weight sensor?

Anyway, although I've technically had more problems with my Cobalt than any of the other cars I've owned (even the 200k mi Tahoe that I used to pull a band trailer across the country ), I love the car. It's a blast to drive.

 

If swapping plugs and coils doesn't change the misfire in #1 start first with inspecting the wires going to the coil pack. After that you're looking at a coked up valve that is not sealing well. That's assuming that it doesn't have an uneven sound to it referred to on these forums as the "subaru mod" that indicates something worse.

Seafoaming will not remove carbon build up from the valves. It's not caustic enough.

Parking brake cable adjustment is right under the handle. Lift the console, tighten the cables. That's assuming your rear brake pads and rotors aren't shot to the point where they need to be replaced. Inspect them first.

Air bag light is as you suspected. Make sure the sensor us plugged in tight and mounted right. Might need a replacement. Stop hauling fat girls.

Enjoy the car and post pictures in the intro forum!

 

Thanks for the quick reply!

The Subaru mod, eh? Is that because it sounds like a WRX when it's in cat warmup mode? Because I have noticed that . How bad is that for the car? And why does it work perfectly fine after it warms up?

I suspected tightening the brake would be something like that. Is there a chance I could do something wrong? Like, the cable could be too tight? I just don't want to screw it up. I checked my pads on all four wheels about four months ago and they looked good for a while. I don't think it's pads.

Good advice

 

No, the "subaru mod" is something you would hear at all times, not just cat warmup. It's unmistakeable.

Cat warmup is altered timing and way rich to get the cat up to proper operating temp quicker. Yes, it does sound bad, no it doesn't hurt the engine. I guess it's good for emissions though I'd argue that running it rich is no better for the environment than letting it warm up slower.

You could over tighten the cables I guess. Just go a little at a time.

 

Ok, so I can rule the "Subaru mod' out. Thanks for the advice. You've already been more helpful then the GM technicians I've talked to over the phone about this misfire problem. They literally just told me (and this was while my car was still under warranty, mind you) "we don't like to work on Cobalt SS's because kids beat the **** out of them and it's your fault that you have a problem with it. Come pay us $500 to tear it apart." I mean, I understand that they are kind of a poor mans race car, but that doesn't mean that I caused the issue just because some 18 year olds don't know how to maintain their cars and then try to warranty them.

Anyway, I'll check the wires to the coils after work and see what's up.

Other than my stated problems, is there anything else out of the ordinary that I should change or check at 53k miles?

 

Maybe change the cabin air filter. Usual inspection for brakes, tires, control arm bushings, air filter.