Chevy Cobalt Forum banner

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

·
Registered
Joined
·
5 Posts
Discussion Starter #1
I used a diagnostic tool an the code came up for a cam shaft sensor which has been replaced twice already but did not fix the issue.
 

·
Super Moderator
Joined
·
11,821 Posts
What year, what engine?
 

·
Levee
Joined
·
3,210 Posts
If your cobalt is not an SS, it will be a 2.2. If it is turbo'd, it's a 2.0, if it's not and it's still an SS, it's a 2.4 :)

---------- Post added at 03:12 PM ---------- Previous post was at 03:12 PM ----------

Welcome btw
 

·
Registered
Joined
·
5 Posts
Discussion Starter #5
Thank you an it's my brothers car an he is not good with cars, but it's not a turbo if that helps but when you come to a complete stop it sputters an once you get going to 30-40 mph it still sputters but not after that. The engine code brought up cam shaft sensor which we replaced an used the diagnostic tool again an it said the same thing cam shaft sensor so we replaced it again because we thought the first one we bought was bad but it still says the same thing.

---------- Post added at 12:57 PM ---------- Previous post was at 12:17 PM ----------

It's a Chevy Cobalt ls an the engine is a 2.2
 

·
Levee
Joined
·
3,210 Posts
Take the battery and disconnect it for 15 minutes and reconnect it. Should clear everything and do a relearn.
 

·
Super Moderator
Joined
·
11,821 Posts
Does he or you do his Oil change?
 

·
Super Moderator
Joined
·
11,821 Posts
The variable cam engine is very picky about the Oil viscousity. Also does not like neglected Oil changes. Best to use synthetic 5W30.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #10
We already disconnected battery did not clear codes. Also just recently had oil change with 5w30 with new oil filter.
 

·
Super Moderator
Joined
·
11,821 Posts
Cam sensor works fine, it's telling you that the cam actuator is not changing the advance to the desired ECM command. Therefore my guess is one of your cam actuator is sticking due to possible dirt or sludge. Tell him to try a good oil treatment until next oil change. If engine progressively gets to work better then you'll know you're on the right track. Unfortunately if it's a piece of grit in the actuator it will not get better and you will eventually need to change it. But good chance it will get better with a treatment.

---------- Post added at 08:34 PM ---------- Previous post was at 07:21 PM ----------

Extra info: if you like to read.

Camshaft Position (CMP) Actuator System
The camshaft position (CMP) actuator system is an electro-hydraulic operated device used for a variety of engine performance and operational enhancements. These enhancements include lower emission output through exhaust gas dilution of the intake charge in the combustion chamber, a broader engine torque range, and improved fuel economy. The CMP actuator system accomplishes this by changing the angle or timing of the camshaft relative to the crankshaft position. The CMP actuator simply allows earlier or later intake and exhaust valve opening during the four stroke engine cycle. The CMP actuator cannot vary the duration of valve opening, or the valve lift.

During engine OFF, engine idling conditions, and engine shutdown, the camshaft actuator is held in the Park position. Internal to the CMP actuator assembly is a return spring and a locking pin. During non-phasing modes of the camshaft, the return spring rotates the camshaft back to the Park position, and the locking pin retains the CMP actuator sprocket to the camshaft.

CMP Actuator System Operation
The camshaft position (CMP) actuator system is controlled by the engine control module (ECM). The ECM sends a signal to a CMP actuator solenoid in order to control the amount of engine oil flow to a Cam Actuator passage. The pressurized engine oil is sent to unseat the locking pin, and to the vane and rotor assembly of the CMP actuator. There are 2 different passages for oil to flow through, a passage for cam advance and a passage for cam retard. The Cam Actuator is attached to a camshaft and is hydraulically operated in order to change the angle of the camshaft relative to crankshaft position (CKP). Engine oil pressure (EOP), viscosity, temperature and engine oil level can have an adverse affect on Cam Actuator performance.

---------- Post added at 08:49 PM ---------- Previous post was at 08:34 PM ----------

More info...still....
 
1 - 11 of 11 Posts
Status
Not open for further replies.
Top