Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Good afternoon everyone!
My 07 cobalt with 2.2 liter engine just had the cylinder head redone because cylinder #3 exhaust valve was burnt causing misfire. I also replaced the head gaskets, spark plugs, cleaned injectors, replaced timing chain, guides, tensioner, & secondary chain. Once I installed everything, the vehicle started but at idle it runs rough. When I give it gas, it smooths out. Checked codes & P0016 comes up. (No misfires) the cam sensor looks original, so I replaced it with an duralast cam sensor, restarted & the same code came back on. So I took the timing cover back off to make sure the timing was set correctly & it was. Rotated the engine over a couple revolutions & the exhaust came was at 10 o clock, intake at 2 o clock, & crank was at 5 o clock. Put everything back together & the same code. I would appreciate any help in this matter!!! Thank you very much!!!
Only thing I can tell you is if you can view live data check your desired and actual regarding the cam. Also did you do a cam / crank relearn as the computer generally has to know that this stuff has been reset so it knows to change it's learned/default value over time.
Chances are the old sensor may be good.
Also if you've by chance troubleshot the sensor, did the relearn, etc and still have the issue then it can be a bad new sensor, badwiring, dirty pigtail, bent connector pin, signal not coming proper.
My suggestion is go back to the basics. Who did the valves, head gaskets, etc? Was it all done to OEM specs and also checking the TSB's as through the years there could be TSB's that address these type of issues as well.
I'd circle back on the relearn first so the computer knows it had a new visitor on the system, he forgot to check in and let everyone know he's part of the new equation now.
Thank you very much for your response!!! I will definitely look on live data and perform the cam/crank re-learn procedure. I installed the head gasket and timing components after the cylinder head came back from the machine shop. I took my time reinstalling everything and I made sure to torque everything to specifications. I will double check the wiring for the cam sensor as well because i forgot to mention that i replaced the connector to the cam shaft as well. But after I made that repair (this was before the head went to the machine shop), the camshaft connection was good because I only had a code for the misfire on cylinder #3. But I will go back to the basics as you stated just to be sure. There is a TSB concerning this issue:
Condition/concern
Some customers may comment of a service engine light illuminated or a crank and no start concern. DTC's p0016 or p0017 will be stored. This may be the result of the camshaft reluctor that has moved on the camshaft. The reluctor is a pressed fit and is not indexed/keyed to the camshaft, it is an interference type fit. (that is from Alldata. see attachment)
Not sure if that applies to my situation, but i will start with the basics first. This engine runs and actually smooths out once i accelerate a bit, the engine sounds much better. I will check on these things and let you know the results! Wish me luck! Thank you again!
There's a washer on the front of the crank gear that looks like it has a timing mark on it. You must remove this washer to view the timing mark on the crank gear. Iv seen this mistake made before.. Good Luck.
