2007 2.0/SS Cobalt with 77,000 miles. Completely stock except for an intake. I've got two engine codes set, a P0017 and a P0300. The P0017 is the cam/crank sensor correlation and the P0300 is a random misfire. Thinking that the two are related, I'm focusing on the P0017 at the moment.

I've scoped the crank sensor, I get a clean sine wave that varies with engine output. I haven't checked the cam sensor, it's not easy to get a scope probe on. So I'm looking for the wire color code at the ECU to rule out any connection issues.

There are alot of threads on this code for the Ecotec engines w/VVT, which this engine does not have. A few threads mention the timing chain. I'm not getting any chain/tensioner noise, and I want to take the valve cover off as the last step. Some threads mention oil (more VVT related, however) sludge. The oil/filter changes have been regular since day one, occasionally going over.

So I'm looking for suggestions. What else can I use to "diagnose" this code. Is there anything that could cause the ECU to falsely throw this code (something else is wrong)?

 

It could be possible that the timing chain stretched enough to set this code but it could also be the cam sensor.

 

the chain would have to stretch over a 1/4in

op either the engine has jump time or the cps has bad wiring or a bad sensor take the 2 bolts out and do not pull the sensor housing out just rotate it to gain access to the sensor

 

I'm resurrecting this old thread of mine, since I'm at the point where I need to get the car inspected.

I've probed the crankshaft and the camshaft sensors with an oscilloscope, they both have clean signals that vary with engine RPM.

So to check for a bad or jumped chain on this car, what is required? Are there any other possible scenarios that I can check for?

 

at this point your going to want to remove the lower timing cover and the valve cover and inspect the timing marks. not sure if LSJ has a thin metal cover plate covering up the timing mark on the crankshafts like the LNF does just something to look out for. the timing chain also hunts so all of the timing marks only line up once for what seems like 50 revolutions, you are going to have to spin the engine over by hand. crankshaft mark will be roughly 5'o clock exhaust will be roughly 10'o clock and intake roughly 2'o clock