Hey y'all I can't seem to figure out why my car won't start any help would be appreciated. I've frequented this forum since I bought the car in Oct. 2022 first time posting please bare with me.
Back story. 08 HHR 2.2L 120K
Car has been a solid great running vehicle until we decided to sell it, go figure. Drove the car to get the oil changed and bought an air filter to change back at the house. Checked the oil level before I left the place and it was good. Got back to the house removed the Housing and the 90 screws holding it together replaced the air filter and put it back together. Started it drove around the block and CEL pops up. Had it scanned it was the MAF sensor. I forgot to plug it back in. I plugged it in drove back to the house and parked it for the night. Next day fired right up drove to show potential buyer and on the way back the car started acting up. Car idled fine but when I pushed on the accelerator it would bog down. I had to feather it to slowly pick up speed. Made it the half mile back and parked it. Turned it off then back on started and idled fine. Thought to myself dirty in line fuel filter but doesn't have one.
Next day wife gets in the car to show it and she got half mile away and called me to pick her up. Car broke down. I was able to get it started and limp it home. Parked it and shut it off. When I tried to start it I could hear the starter spinning but didn't sound like it was engaging the flywheel. So disconnected the battery and pulled the starter. Bench tested it and Bendix wasnt doing its job.
​​​​​​WHat I've done so far.
Replaced the starter.
changed the battery
Checked and rechecked fuses and relays swapped like relays in hopes something would change. Did not
​​​​​​I can hear the fuel pump and it has fuel @ fuel rail. I did not do pressure test yet
Removed the valve cover and checked timing chain for slack and broken pieces of the guide. None and none
Replaced camshaft sensor then changed it back to the old one because I don't have a way to relearn it.
Yesterday I borrowed code scanner and the only stored code was P0016 pending.
I haven't tried starter fluid because of this code and the fear of damaging the valves. Sorry for the long read trying to give as much info as possible.

 

Welcome to the site, stop trying to start the car, P0016 indicates the timing chain has skipped a tooth or 2

https://www.obd-codes.com/p0016

 

Would replacing the camshaft sensor trigger this code?

 

No the sensor is doing it’s job telling you the camshafts and crankshaft are out of time.

First possible cause is …
Causes may include: Timing chain stretched, or timing belt skipped a tooth due to wear Misalignment of timing belt/chain Tone ring on crankshaft slipped/broken Tone ring on camshaft slipped/broken Bad crank sensor Bad cam sensor Damaged wiring to crank/cam sensor Timing belt/chain tensioner damaged

 

What Oldblue said, don't crank it over anymore, you could cause catastrophic damage, hopefully hasn't happened yet.

You need a new timing set.

 

I pulled the valve cover and guide that sits over the timing chain to visually inspect the chain. There wasn't any sag or movement with the chain. I guess I have a chicken or the egg scenario. This code wasn't present on this first scan while it was running. I've had the battery disconnected at least a dozen times (does this clear the codes?) and installed a new camshaft sensor. The newest scan as of yesterday pulled this one and only code.
How do I rule out the timing chain completely without replacing it?
Thank you for your time I Do Appreciate it.

 

You can reuse the old streched chain and worn guides, and retime it, but why go to all that work.

 

Yes, every time you disconnect the battery, you clear the codes and reset the I/M monitors.

 

If you need a smog to sell, stop clearing codes. It could take 2 weeks to run all of the I/M tests.
The P0016 pending might come from diddling around with the crank sensor. Worry when it sets the CEL .
Why did you replace it to begin with? Crank or cam? crank needs relearn cam does not, neither fail frequently.
Did you look at the chain while turning the engine?

 

Why did you replace "the" camshaft sensor? Which one? (As Donbrew points out, there is only one.)

There is no good explanation for a P0016 in a non-VVT car other than that the intake cam sprocket chain has skipped a tooth or two. That the chain is found to be tight now is mildly reassuring but falsely so. A bad tensioner can allow the chain to be sloppy sometimes and sloppy sometimes. Now that it won't start, valves could be bent.

With the valve cover off you can peep down the front of the chain case and inspect the front guide for damage, but what's the point? You're going to need to take the engine cover off anyway to retime the chain, and figure out why it jumped in the first place. Having got that far you might as well spring for the full kit to do a complete chain job.

But the confounding problem is you could fix the chains and find out you've got bent valves. Maybe someone knows how to check for this without pulling the head or doing a normal compression check to this can be determined before messing with the chains.

If money's tight and the engine has been very well maintained with no "extended oil change intervals," you could examine all the parts and keep the ones you're willing to gamble are good. Your 2008 came with an "old style" timing tensioner that definitely needs to go. Also, the new oil squirter has a larger orifice. Right now, I'm of the mind that every Ecotec ought to get ZZP's new upgraded front guide.

I once replace nothing but the timing tensioner in a 2008 2.2 that had a noisy chain, and got away with it. But it hadn't jumped time yet.