Chevy Cobalt Forum banner

Status
Not open for further replies.
1 - 11 of 11 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter #1
Okay. I have a 2009 Chevy Cobalt LT (XFE) with 48,000 miles. It is a 5-speed Manual. I've owned it for about a little over a year. Been a decent car. Within the past month it has developed some problems when accelerating. The CEL is not on.

While I accelerate in first and second gears, it kind of jerks and acts as if I'm letting off the peddle and back on again in rapid motion. The RPMs don't fluctuate too drastically and this only lasts a few seconds, until the RPMs get high enough that I need to shift. Occasionally it does it in 3rd, 4th and 5th gears but not as often. Also, it's not every time either. It's very intermittent. And it seemed to not act up when it was extremely cold a week ago (10F-20F). I change my oil on a regular basis and recently changed the engine air filter. I haven't changed the spark plugs or fuel filter.

I've researched on this forum and various websites from google. All say it could need new spark plugs, possibly a new fuel filter or (and I hope not)...a new clutch. I don't ride the clutch and am not new to driving a manual car, so I know how to drive one. Is it possible the clutch could be going out at 48,000 miles? I'm probably going take it to a shop and have them look at it, but I thought I'd ask you guys first. Thanks for any information!!!
 

·
Registered
Joined
·
1,145 Posts
I too have an XFE, but an LS version, same year. Mine has 83k miles and it does that very rarely, but no CEL as well. Its not a huge concern to me since electronics are being used for the accelerator pedal.

If you are using other types of spark plugs other than AC Delco Iridiums (OEM), that may have affect to your hiccup. I use Nippon Denso Iridiums and have no issues so far, but once in a blue moon, it feels like my foot slipped off the pedal for a tad second. It may also have to with the cold weather.

For the shifting of 3,4, and 5, ensure you don't attempt to floor it on a very low rpm (below 1500ish), the power curve is very low on bottom end.
 

·
Registered
Joined
·
6 Posts
Discussion Starter #4
There is a simple procedure to test the clutch but I can't remember it at the moment.
I tried taking off in 1st, and then going into 4th and even 5th gear to see if the RPMs and engine would continue going, and they did not and it bogged down like it should. I also parked, and put it in 2nd gear and let off the clutch to see if it would stay running, and it the engine cut off like it should. So I don't think it's the clutch. it started out very rare and intermittent, but has got worse here recently where it's a huge annoyance. I think I'm going to take it in tomorrow and see if it's something simple I can fix myself.
 

·
Registered
Joined
·
1,145 Posts
Well the clutch pedal should have 1/2-1" of free play, then its either off or on. You may have a bad throw out/pilot bearing and/or your fingers on the pressure plate may have no clearance from the bearing, should have .050"-.100" of clearance.
 

·
Registered
Joined
·
6 Posts
Discussion Starter #6
Well took it by Midas today (just because I usually get my oil changed there). There are no codes...he thinks someone might have wiped them clean (maybe my wreck a year ago had something to do with it?). And it apparently ran just fine when he test drove it...he said everything appears okay. He said it shows the air flow sensor failed at one point but works fine now. I drive it...it's driving fine for about 10 mins and has been cutting out every since. He said to bring it back if it gets worse and they'll drive it with me. So annoyed right now. Nobody seems to know what's wrong with it. Maybe I'll take it into the dealership.
 

·
Registered
Joined
·
6 Posts
Discussion Starter #7
Well, just a day later and the CEL has magically appears. It almost seems as tho, after it came on the car stopped acting up. We'll see next time I go for a drive. I shall keep yall posted.
 

·
Registered
Joined
·
1,145 Posts
Can midas provide you with a p**** code for what problem it is? That will help out a lot to some techs here :)
 

·
Registered
Joined
·
6 Posts
Discussion Starter #9
Well Midas had said it previously had a Mass Air Flow Sensor code, but it had been cleared.

Fast forward, the CEL came on so I hauled on over to the parts store and had it read. He said it was a mass air flow sensor. Car was still running rough (tho not as bad when it was -10F here).

Today I took it into Midas and they called and said there were two codes present...
P0101 and P0011. They suggested I replace the Mass Air Flow Sensor and Camshaft Sensor, which I did. It appears to be running fine now. It had a few hickups, but nothing like before and I assume it'll resolve it's self.
 

·
Super Moderator
Joined
·
11,821 Posts
I can't believe 2 sensors went at the same time. Process should have been, clean MAF, try it out. If the same change MAF, try it out. If the same change cam sensor. Because now you don't know what caused or cured your problem.
 
1 - 11 of 11 Posts
Status
Not open for further replies.
Top