Chevy Cobalt LT 2.2 RPM Bounce Issue

Asked by Cayden May 19, 2019 at 07:57 PM about the 2009 Chevrolet Cobalt LT Team Canada Edition Coupe FWD

Question type: Maintenance & Repair

I have a 2009 chevy cobalt lt 2.2 litre engine. It has many mods that were not
done by me, I'm the second owner. It has 105000km. It has a supercharger,
coolant for the supercharger, some gauges that aren't hooked up, fully
custom exhaust. It was essentially modded to be a Cobalt SS. The problem
that I'm having has been going on for some time now. Whenever I'm driving
and depress the clutch fully to make it go into an idle state, at first the RPM
will bounce down to around 500-600 rpm and come back up to its normal
idle(around 750-900). Sometimes itll bounce around in the 500-800 range
and come back to normal. When this happens i can audibly hear the change
in sound from the exhaust, sounds like its close to stalling. I've tried cleaning
the throttle body, even completely replaced it, changed plugs and just some
general cleaning around the engine bay. I don't think there's any vacuum
leaks. Nothing noticeable anyway. When just idling the car runs completely
fine, it's only when i depress the clutch completely when coming to a stop
sign or something that it bounces around. It appears that it's getting worse,
only thing i can think of is that it might have a bad o2 sensor. both the o2
sensors are pretty jumpy as far as readings go, im not sure what they're
exactly supposed to read anyway. Could also possibly be MAF sensor
related. Thanks

1 Answer

18,645

Could be a lot of things. If its been partially modded by others and there are dangling wires and things not hooked up it could be most anything. I'd go through everything and try to determine what you're working with before spending any money on parts. Try scanning it for trouble codes. There may be some clues there. Also be careful when you do get it going. A 2.2 is not designed to be supercharged so go easy on it. On the other hand, it may actually be a 2.0, which was. Good luck. Sound like it could be a fun car if you can get the bugs worked out of it.

Your Answer:

CarGurus Experts

  • #1
    munron
    Reputation
    8,410
  • #2
    John Carson
    Reputation
    2,290
  • #3
    MoGo
    Reputation
    1,990
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Chevrolet Corvette
26 Great Deals out of 1,018 listings starting at $19,500
Used Chevrolet Impala
10 Great Deals out of 114 listings starting at $3,531
Used Chevrolet Malibu
50 Great Deals out of 1,186 listings starting at $1,495
Used Chevrolet Camaro
25 Great Deals out of 341 listings starting at $10,500
Used Chevrolet Colorado
27 Great Deals out of 1,410 listings starting at $6,800
Used Honda Civic
158 Great Deals out of 3,439 listings starting at $2,495
Used Chevrolet Silverado 1500
228 Great Deals out of 5,946 listings starting at $3,995
Used Toyota Corolla
118 Great Deals out of 1,936 listings starting at $1,995
Used Chevrolet HHR
7 listings starting at $3,499
Used Ford F-150
307 Great Deals out of 15,379 listings starting at $1,954
Used Chevrolet Equinox
68 Great Deals out of 2,810 listings starting at $3,888

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.