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Discussion Starter #1
So I change the belt in my girlfriends Cobalt 2.2 and now it shakes while idling.
When I first started it up there was a flashing check engine light but that was a week ago and it doesn't seem to be flashing at the moment.
I don't currently have a way of checking the codes was hoping somebody recognized the problem from the symptoms.
Could I have lined up the motor mount badly when re-installing it?
 

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So I finally got the codes read.
Had 10! Couple evap, misfire and an o2 sensor which I believe those are all secondary.
The Two that stand out as a real issue are a coolant temp sensor and a camshaft position sensor.
Anybody have an idea of which to start or how to check? The CPs is just a resistance check right?
 

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Did you disconnect the car battery before changing the belt?
You probably disconnected a sensor by accident or on purpose to change the belt, or you blew the EXH fuse somehow by either pinching a wire orlby leaving a connector hang loose and touching.

 

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Discussion Starter #4
Checked the EXH and it's all good. Checked them all to be safe.
I check the CTS wire and it looks ok I can't find the camshaft pos sensor.
 

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Maybe you broke the engine ground at the lug if you lifted the engine to change the belt. It's the one in the front where the transmission meets the engine.
 

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No thats fine. I did buy a coolant temp sensor just to try something, I know that was the issue with my fiero whioch did similar things although it was also running crazy rich.

The code I got for the Camshaft position sensor was P0340 but it looks like the car doesnt have CPS

---------- Post added at 11:03 AM ---------- Previous post was at 10:34 AM ----------

So temp sensor replaced and no change.
Cant find any broken or unconnected wires/sensors. Could this be a bad crank shaft position sensor showing up as a cam shaft sensor?

What about bad coils?

Should I replace the plugs as well perhaps it ran a bit rich and fouled them up?
 

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Not if you don't have misfire codes. What year is the car? 2007 and up have cam position sensors.
 

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Discussion Starter #8
It's a 2006

---------- Post added at 11:48 AM ---------- Previous post was at 11:42 AM ----------

Should I bother with spark plugs?
Something I just noticed, while in park if I idle the engine up to 2k the CEL stops flashing and just stays solid. While driving even at 2k rpms it just keeps flashing

---------- Post added at 11:53 AM ---------- Previous post was at 11:48 AM ----------

Now I am just getting P0300 (multiple misfires) and P0340 (cam position sensor)
Readings after replacing the CTS

---------- Post added at 12:02 PM ---------- Previous post was at 11:53 AM ----------

So I ordered a crank shaft sensor to give that a try.
Any other suggestions in the meantime would be great
 

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If it was the crank position sensor you wouldn't be able to start your car after you shut it down. What puzzles me is that this started after you changed the serpentine. Multiple misfire suggests crank sensor but the whole thing doesn't compute.
 

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Discussion Starter #10
The only other thing I didn't mention is that it sat for a couple weeks but I didn't think that would be such an issue.

Is it possible that the crank position sensor is just giving a slightly off value to the ECU causing it to misfire?

The crank sensor is only $20 and there was a guy at the parts store that said it worked for him in a Saturn with a 2.2 ecotec
 

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For $20 it's not a big lost. Crank sensor is a bit hard to get at, i even think the procedure calls for removal of the starter to get to it. Now I've been wrong before and just going by memory.
 

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Discussion Starter #13
Well I finally replaced the crankshaft position sensor and still the same problems
Runs rough (misfiring) and gives a P0340 engine code (bad camshaft position sensor)
Going to continue to scour the net I guess if anybody has heard of this any suggestions would be great

---------- Post added at 11:44 AM ---------- Previous post was at 11:41 AM ----------

Geez I never saw the second page.

BankerBalt, how do I do a crank relearn? Never heard of such a thing
 

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Discussion Starter #14
Ok so it's been a while but I figure I would check back in and share my solution.
When my friend swung by with his nifty scan tool to relearn the CKP we discovered that the misfires were on cyl 1&4 and the cam pos sensor uses 2&3
This got me suspecting the coil/ignition module and I started with the ICM and that did the trick!

Thanks to Coby7 and Bankbalt for the help
 
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