jkb242

Got affirm quote to replace valve timing chain, including chain and guide kit with reluctors etc.
$1200 leaving water pump and main chain which would add another $300. Ship estimates are ~7hrs(per the labor estimate guide).

Does this sound reasonable?

ruley73

What year? Which engine?

jkb242

2013 2.4L

thanks

dtcassist

I would say on the high side but not unreasonable. Not knowing location, labor rate/parts cost etc. Assuming it's at a GM dealer?

I have to ask though, what's the reason for replacing? Is it making noise, or is this related to your previous post about a check engine light?

jkb242

Indeed it's all the above. Many months ago, the position sensors were both throwing codes then replaced both. Normal again for some time then recently the P2090 code which was associated with the exhaust timing. Engine runs good no noticeable issues just continued showing the code. Cleaned and checked sensor and electrical contacts reset code but code came back within a few miles. Over the last year I have heard what sounded like a bit more engine noise than I would expect especially after first start in the AM but after running it seemed to sound normal to me but I may have gotten use to the elevated sound after so long. I was never aware of any chain stretching for wear at this point with the history of these engines. I looked more deeply into this I began to discover this issue after ~70K or more miles. I sought input from another very trusted forum from a person who actually has the same engine in another GM model. Made him aware of the history above, and he was convinced that the valve chain was the culprit. I was encouraged to do this repair myself since I'm retired and felt pretty confident completing the actual repair until I saw the difficulty of access with this model. Engine mount removal and otherwise necessity to have access from beneath the vehicle. Given the complications I reluctantly decided do turn this over to a shop I have been using for other repairs I cannot complete. The shop is honest and have earned my trust and did not care to go to the dealer given horrible past experience. Maybe I should have gotten an estimate at least from a dealer but I presumed that there couldn't be that much difference and wanted to patronize the owner operated shop.

Unfortunately, I learned today that the VVT cam reluctors were not being replaced so I requested that to be added to the mix leaving off the crankshaft chain and the water pump since the primary issue is the VVT components. I'm sure the kit that includes the VVT sprockets will add $ but I was advised and agree that leaving the original ones is not a good idea to get beyond another 50K. So my cost for this is closer to $1500 now but I think this is the right way to go given this common failure history with this engine. My extended warranty expired about a year ago. Nice ugh? Thanks for your comments and please feel free to offer additional insight.

dtcassist

GM has had some issues with timing chains and tensioners and stretching, but I'm not aware of a well known issue on the 2.4l. (could be just haven't come across it - but the V6s yes absolutely have had some serious timing issues) If you do in fact have noise that is unacceptable coming from the front of the engine then it may well be the cause. Personally I wouldn't push to replace every last thing under the cover, unless there is an obvious issue with it. They aren't made to be maintenance items like some of the cars with timing belts.

But, a stretched or out of time timing chain (or related tensioners guides etc) if bad enough can set a code but it will be a P0011, P0014 P0017 or the like - saying timing does not match or system performance. A P2090 on the other hand is a circuit code. For this code It doesn't know or care what the timing situation is, the ECM just knows it's not getting a signal back from that component. So even if the component it refers to has been replaced - you've still got all of the wiring from there back to the ECM that could be the cause. And new timing chain mechanical components aren't going to help.

As you've seen the timing chains and related components are not a cheap or easy job - I'd hate to see you go through all that and still have the same fault. That's the value of diagnostics, sometimes it seems like a lot of money but it can save you a lot of money and frustration by digging down to the root of the problem first.

Gumby22

I’m in agreement with dtcassist on this - the quote isn’t too high, but replacing the mechanical components is unlikely to resolve this issue.

Basically the code means that the PCM isn’t seeing a low reference (ground side) voltage returning from the exhaust actuator solenoid. If the solenoid has been replaced (and assuming the new one wasn’t bad out of the box) then there’s either a short to ground or open in the wiring between the solenoid and the PCM.

On the 2.4 this isn’t a hard circuit to trace - you can start by just inspecting the harness for obvious damage. If the looming is torn or there’s any areas that have been rubbing/resting against anything are the first places to check. You can also inspect the terminals at the solenoid connector to see if they’re spread out, causing weak or intermittent contact.

A couple points FYI:

1) MOST issues with the VVT system are unlikely to cause drive ability concerns. Whenever a code for the VVT system is set, it’s disabled until it’s repaired. The actuators for the system have a default “at rest” position that allows the valve timing to function as if it were a basic timing chain and gear, so the crank and cams rotate in sync with each other (I’d have to double check but I think the base mechanical timing is 0*).

2) You mentioned replacing the reluctor rings - I understand your reasoning for wanting it done, but I don’t think it’s a good idea.

On the 2.4 and the 3.6, some of the cams are known to twist, or to allow the reluctor rings to rotate from their original positions, which results in cam to crank position not plausible codes (P0016 & 17). Since there’s no certainty on which cams have this particular problem, or what exactly causes it, replacing the reluctor rings may actually cause it to happen. Then you’ll end up paying for new cams anyway.

If the cams are in good condition, I’d recommend leaving the reluctor rings on them.

Good luck.