Current Sonic Issues... idle and AC problems

[Maddmatts]

Auto transmission right? I recall some people having similar idle issues caused by the rings in the clutch packs being made too thin. Their proper name eludes me at the moment.

Some have also claimed it was caused by some weird feature of the transmission shifting to neutral while stopped but not working properly. And could be programmed out by request at a dealer.

Some idle issues were also caused by sparkplugs that were gapped well outside of tolerance. It sounds like they were never really checked during the manufacture of the 1.4T.

 

[illsonic]

there is a tsb for this problem i just had my car in the service dept a few days ago the transmission has to be torn apart and i beleive they told me new clutches have to be installed i was told its an 8 hour job i have not deceided if iam doing it or not atleast i know its not the engine its the trans

 

[ChrisJ]

there is a tsb for this problem i just had my car in the service dept a few days ago the transmission has to be torn apart and i beleive they told me new clutches have to be installed i was told its an 8 hour job i have not deceided if iam doing it or not atleast i know its not the engine its the trans

Better do it while you have a warranty to cover it.

The trans is just as important as the engine so saying you'd rather it be the trans doesn't make sense.

 

[countrydrivin05]

there is a tsb for this problem i just had my car in the service dept a few days ago the transmission has to be torn apart and i beleive they told me new clutches have to be installed i was told its an 8 hour job i have not deceided if iam doing it or not atleast i know its not the engine its the trans

Yep... my friend who is a Chevy journeyman confirmed it... I found out that he has known for a little bit but never told me LOL. Well time to schedule a dealer appointment Monday.

 

[Cinsue]

there is a tsb for this problem i just had my car in the service dept a few days ago the transmission has to be torn apart and i beleive they told me new clutches have to be installed i was told its an 8 hour job i have not deceided if iam doing it or not atleast i know its not the engine its the trans

Nice to know. This will give me something to point the service dept to. Thanks!

 

[Inferno]

I don't have a auto but If I did useful information would go here.!

 

[Cinsue]

I've been looking, but can't find the TSB on this. If anyone has the number, I'd appreciate a share! Thanks!

 

[bandita52]

i have a sweet smell coming from my vents when i have my ac on sometimes plus when i push on the gas it feels a bit sluggish. is this a know problem with this car. any suggestions. i have the 1.8L auto sedan.

 

[Chevrolet Customer Care]

i have a sweet smell coming from my vents when i have my ac on sometimes plus when i push on the gas it feels a bit sluggish. is this a know problem with this car. any suggestions. i have the 1.8L auto sedan.

Would you like me to check your VIN? I can also call and make a service appointment with your local dealer if you would like. Just let me know by private message. I am here to help!

Jackie
GM Customer Care

 

[illsonic]

what i mean by my comment is atleast i know the engine is running as it should be . i will get it done if i dont trade for a 2014 sonic ,iam waiting to see what the changes are for the 2014 model

 

[countrydrivin05]

Update

Got my car back yesterday from the dealer. Boy am I glad to have my 1.4L Turbo back (the power the power, LOL). I had a 2012 LTZ 1.8L sedan for a loaner... and its OK but not as nice as my car, but that's my opinion.

Its too soon to say whether or not the new transmission plate kit has fixed the problem (the weather is too cool today anyway for it to "act up"). The bulletin number is PI0928 and from what my mechanic buddy said they replaced some of the clutches with ones of a different material. I didn't get to see the bulletin in detail but that is the main idea of it.

On a good note, my trans fluid has been changed 2x in about 3K miles, LOL... she'll be good to 60K now (have 14,8xx miles now) and my one seal that was leaking was replaced again too.

Oh and about my AC problem... since each motor has a different compressor part number, I cannot really compare them directly, but I am just assuming because the 1.8L is a bigger motor is why I never felt it when the AC cycled on and off. So, I guess me feeling the compressor cycle on and off is normal for the one on the 1.4L engine.

I'll post an update again once the wacky weather in STL finally decides to warm up for Spring heading into Summer.

 

[Cinsue]

Got my car back yesterday from the dealer. Boy am I glad to have my 1.4L Turbo back (the power the power, LOL). I had a 2012 LTZ 1.8L sedan for a loaner... and its OK but not as nice as my car, but that's my opinion.

Its too soon to say whether or not the new transmission plate kit has fixed the problem (the weather is too cool today anyway for it to "act up"). The bulletin number is PI0928 and from what my mechanic buddy said they replaced some of the clutches with ones of a different material. I didn't get to see the bulletin in detail but that is the main idea of it.

On a good note, my trans fluid has been changed 2x in about 3K miles, LOL... she'll be good to 60K now (have 14,8xx miles now) and my one seal that was leaking was replaced again too.

Oh and about my AC problem... since each motor has a different compressor part number, I cannot really compare them directly, but I am just assuming because the 1.8L is a bigger motor is why I never felt it when the AC cycled on and off. So, I guess me feeling the compressor cycle on and off is normal for the one on the 1.4L engine.

I'll post an update again once the wacky weather in STL finally decides to warm up for Spring heading into Summer.

Thanks for posting this!! Hoping the fix worked!

 

[countrydrivin05]

Thanks for posting this!! Hoping the fix worked!

The fix has worked so far and also the upshifts and downshifts are much smoother too... so overall much better in drivability.

 

[bdowne01]

I too have a nasty rough idle while in "D" on my 1.8 AT Sonic, and I too also put it into Neutral at lights to get it to stop. Also, the AT seems to randomly "grab" slightly while idling at a stop--just for a split second--and makes it feel like the engine stumbles for a moment.

Local dealer also said it's was "bad gas" and to put "good stuff" in. They put some GM fuel system treatment; 4 tanks later with Chevron 91 octane, and it's still doing it.

Are you guys with this idle problem also experiencing a strange "negative" pull when slowing down to a stop as well? It's kind of hard to explain, but when coming to a stop from say 45 MPH or so, you can really feel the trans sort of engine-braking, but not consistently. Actually makes it kind of hard to judge where to stop--and I find myself either under braking or over braking... Never had this problem with my old Aveo.

I've got my Sonic due in to get a clunky passenger-side strut replaced (though the dealer never called me back today.. ugh), trying to decide whether I bring this up too or not.

 

[Sonic_RS_13]

So I am guessing no one has found a fix to the rough engine running while in drive at stop lights?

 

[bdowne01]

Possibly. My car has been at the dealer for about a week. I mentioned the rough idle occurred regularly, and had the mechanic take it out for a drive. We sat at a red light, lo and behold it idled terrible and even felt like it missed.

Later they called to say they found some fuel system trouble codes posted by the computer (though there was never a check engine light) and they were re-flashing the computer.

I'm picking it up on Monday. I can report back on how it works out.

 

[SuperFudd]

There can be error codes without the light being set on.

 

[Chevrolet Customer Care]

Possibly. My car has been at the dealer for about a week. I mentioned the rough idle occurred regularly, and had the mechanic take it out for a drive. We sat at a red light, lo and behold it idled terrible and even felt like it missed.

Later they called to say they found some fuel system trouble codes posted by the computer (though there was never a check engine light) and they were re-flashing the computer.

I'm picking it up on Monday. I can report back on how it works out.

Hi bdowne,

I'm happy to hear that your dealer was able to find the issue. Please keep me posted on your results. Don't hesitate to reach out via private message if I can be of any assistance

Best Regards,
Crystal L
Chevrolet Customer Care

 

[Sonic_RS_13]

Mine comes and goes, hopeing the warmer weather will make it come out so I can show the dealership. Running a tank of 91 octane to see if it helps. As far as AC on and off it doesn't affect mine at all. Best of luck to y'all.

Should I put my tune on hold till I get this figured out? What about other Mods? Just let me know y'all's opinion on this.

 

[Chevrolet Customer Care]

Mine comes and goes, hopeing the warmer weather will make it come out so I can show the dealership. Running a tank of 91 octane to see if it helps. As far as AC on and off it doesn't affect mine at all. Best of luck to y'all.

Should I put my tune on hold till I get this figured out? What about other Mods? Just let me know y'all's opinion on this.

Please keep me posted and send me a private message to let me know if you have any questions or need my assistance.

Jackie
Chevrolet Customer Care