So I heard back from the dealer this morning. They need the car "till Friday" now. Top end of the car is pulled apart and all they would say is they "suspect valve issues".....then the also inform me they are replacing the cat. This made no sense to me. Why would the the cat need to be replaced at 40K KMS.....then it dawned on me, the cats were probably destroyed from the "3 deep carbon cleanings" they tried first.

This I assume is sea foam or some variant of it. I would not think this type of thing being done repeatedly would be good for the cat or any part of the emissions system.

I have to go to get a few things out of my car in the next day or 2 so I it will be interesting to see how "pulled apart" my top end is. I honestly don't thing they really know whats wrong judging by how vague the service guy was being with me on the phone.

 

time for you to maybe switch dealerships before they mess up something else

 

I will let it play out. Its under warranty so I'm not to worried about it.

UPDATE:

Well, got a call this morning and my car is ready. It was a "lifter/misfire issue". They did 3......yes 3 Carbon cleanings fixed the lifter and also replaced the spark plugs, replaced an injector, a coil pack that was fried, and had to replace my Cat.

I'm guessing the 3 Carbon cleanings they did first were what damaged the plugs and destroyed the cat. The injector was the first thing they thought was wrong, which ended up not being the problem obviously. They also did the recall for the ignition cylinder lock.......which I laughed at because it was towed to the dealership 2 months ago because the cylinder failed and had the recall work done then. Kind of worries me about their record keeping skills.

Car is back up and running.


Going out car shopping this weekend.

 

Guess who's car is back at the dealership with another miss fire issue! This time it is cylinder #4 instead of all of them LOL. Top end is being ripped apart again and tech says he is pulling everything apart and cleaning the carbon by hand this time. He says prolly Tuesday before I get my car back. This is just unreal and I am fed up.

Dealership has been very cooperative and I have a loaner but I can't be going through this all the time. Car only has 46000 km's on it. I have never had issues like this with a car before. The joys of Direct Injection.

On a side note the tech told me he just finished replacing the top end on a Cobalt SS/TC with roughly the same km's as mine due to a broken lifter that was caused by .....you guessed it carbon build up.

 

Hrm. I do three part injection cleanings every 10k miles, and my cat isnt bad. They prolly replaced cat due to the misfire/o2 bad readings. I replaced coils at 70k miles cause i found em on sale.
Not quiet sure what they are doing. Ask if they did a compression test. If it passed its electrical problem. Might be bad gas, injector, plug, etc

 

I'm not ruling anything out but they did replace all the plugs last time. They tested the coils and had to replace one. Tested and cleaned the injectors and replaced one. They did 3 Full carbon cleanings last time along with replacing the cats. Gas is not the issue. I'm also certain the cats were destroyed from running all that cleaning fluid through the motor 3 times along with what ever carbon was burt off in the process.

Tech is certain it is Carbon build up on the lifters and valves that is causing the issue. He says he has had to do a full teardown on the top ends of a few LNF's and clean everything by hand or replace broken parts over the past little bit for this same issue. It has always been Carbon build up. This is a widely known issue on any Direct Injection motor. I'm just surprised it has happened so soon. This is something I would expect at the 150000 KM mark not the 45000 KM mark.....twice.

 

I'm missing something. I can see the carbon buildup in the valve area( a known issue because of the DI system.)
Why would there be carbon buildup in the lifters? Wrong side of the combustion chamber for this to happen.
Someone please explain this one.

 

I may have miss understood what he said about the lifter's and carbon. Unless carbon build up on the valves would cause the lifters on the other side to stick?

 

Hrm. The fuel injection service, actually should clean the cat, not hurt it. What might have hurt your cat was the build up. But like i said i run it alot in my car and have no cat problems.
As far as the lifters... im not sure. What kinda fuel do you use?

 

Shell 91 since the day I took delivery of the car. I figure the same as you that it was what ever was cleaned out clogged the cats.