Camshaft position sensor Chevy Cruze

I have a 2012 Chevy Cruze LS. I reached 100,000 miles so I took my car to have the timing belt replaced along with the water pump and what not. When I got my car back the check engine light was on, I took it back and they said it was on prior, I told them it definitely was not. Told me to bring it back the next day. The error is “camshaft position sensor”. My car seemed to be driving fine at first, then this morning when I went to start it, it didn’t want to and hesitated. I turned it off and tried again and it came on, but sounded much louder than normal and maybe even a little scratchy? Idk! I’m not savvy in the car department, but I’m super paranoid that this is going to be a big deal and will cost me even more money! Anyone know what it could be?

I don’t know the exact code you had . . . did anybody write it down for you. There are several different kinds of codes related to this sensor

I suspect the shop did not properly plug the sensor back in, or it got damaged during the timing belt replacement

here’s my reasoning. If the cam sensor sensor is faulty . . . or not plugged in . . . the engine will typically start, but it will take considerably longer to do so

I’m pretty sure it was P0340? I could be wrong as I didn’t write it down. I hope it’s something that you’ve mentioned as it doesn’t sound like it’s a huge deal! Thank you so much for responding!

P0340 . . . “Determines if a fault exists with the cam position bank 1 sensor A signal”

Unless the engine uses variable valve timing, you’d think the only function for the cam sensor is to tell the ignition system which crank cycle to fire on. Without a functioning cam sensor it probably fires on both, rather than on alternate cycles. Seems like that wouldn’t affect engine performance much. There could be a fuel injection component to the cam sensor function I suppose, and that might be the reason the engine isn’t running as smoothly.

A faulty time belt install that didn’t get the timing marks aligned properly or the belt tension correct is another possibility. If so, worse case, that could cause major engine damage. OP should phone up the shop and ask if they think that could be the problem, and if the shop thinks the car should be towed back rather than driven?

That often results in a different kind of fault code . . . a code that alludes to correlation

I took my car back to the shop this morning. It didn’t have any trouble
starting and wasn’t running loud this time. It drove fine, I asked the
mechanic and he said they were thinking it’s just the sensor. Should know
more soon! Hoping for the best! Thank you for the responses! I panic quick,
fast and in a hurry!

Yes, there is a fuel injection component. With a sequentially time injection system, you need the cam sensor to determine TDC of the #1 cylinder so you can inject in-sequence as well as fire the spark plugs in sequence. At least with the plugs, firing into the exhaust stroke doesn’t matter. injection fuel with the intake valve closed does matter. So the engine controller compensates by not knowing where #1 is by injecting fuel twice a cycle based on the crank sensor.

It runs, but not as well.

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My Corolla squirts all the injectors each pulse, so some of them must be squirting when the intake valve is closed. That method seems to work ok on that car. But the intake manifold and cylinder head is probably designed to handle that, and on cars designed for sequential injector sequencing, probably not so much…


come on


Did I say something that doesn’t make sense? oh oh … lol … what was it?