Hello All,
I usually post on this forum about my 51 Chevy and have gotten terrific help but now I need your help with my sister's 2013 V6 Camaro. It seems that with only 34,000 miles the engine is, according to the Chevy dealer in St Augustine, Florida, all carboned up. It is in the shop now and the extended warranty company refuses to pay for the repair. Any advise from you all would be very much appreciated.
I also would like to find a good repair shop in that area for her to perhaps move the car there for the repair since she does not trust the people at the dealership. Every time she talks to them they give her a different story including an estimate of $10,000 to replace the engine!!!
Any advice/help is greatly appreciated.
Jeff

The only advice I can give is to do a Youtube search. Seems that is a common problem and there are lots of post regarding the subject from DYI methods to professional ones that don't involve engine disassembly.

Thank you for the reply. Unfortunately, this dealership has already said that they have partially disassembled the engine to diagnose the problem (at least that's what they said, although my sister has not been shown anything). I think she is being led down a worm hole that will cost to dig out from.
Jeff

I would think that when she brought the car in and explained the problem they would have given her an estimate for diagnosis. Perhaps a VCCA member in that area can recommend a shop that they trust . If so I would surely consider getting a second opinion even if it means towing it to the second shop. Also she should get a written estimate and not verbal listing the problem and repairs needed and the warranty that would apply to the repairs. It would be interesting to know why the extended warranty does not apply.

Thanks for the info. The extended warranty company denied the claim because they said that this is not a "mechanical failure". I am hoping another VCCA member will chime in with a shop that can be trusted. She certainly would be willing to have the car towed to another shop if she was reasonably sure that they also won't try to fool her. I also agree that a written estimate should have been given. Unfortunately, when a single woman goes in for service they think that they can take advantage.
Jeff

By carboned up do they mean the combustion chambers are full of carbon or the engine in general is sluged up due to not changing the oil? I have seen cars that were neglected and oil not changed have the engines die at about 30,000 miles.

Chev Nut - thanks for responding.
According to what I'm told:
1. The engine is carboned up, not sludged.
2. My sister is very fastidious about maintenance. Oil has been changed at regular intervals.
I believe that if an engine is not warmed up enough and is hardly run at higher rpm's it can cause carbon to build up. But to be told that the engine is "blown" (their words) at 34,000 miles seems absurd.
Jeff

Being a V6 the engine will be a 3.6 , an engine used in many GM cars. What did carbon up in this engine is the intake valves, the carbon built under the intake valves. GM made a solvent to lossen the carbon.. It saved the expense of removeing the heads (and valves) and cleaning the carbon.
This was caused by short trip low speed driving and not using a "top tier" gas containg a detergent.
I never saw an example that it blew an engine but I suppose it would be possible if it got go bad that it prevented the valve from closing and it was hit by the top of the piston and could "blow the engine".

I agree that carbon build-up on intake valves can create lots of issues. There are lots of removal techniques that do not require extreme engine disassembly. I had an Audi that was recalled so they could remove the intake manifold and glass the install valve with walnut shelves to knock off the carbon. I have use the water technique as well as fed Seafoam in to knock out carbon.

Most of the problems I have encountered and am aware of were with “indirect injection” engines. In those engines the fuel is injected into the air stream before the intake valve. So the carbon can build up on the intake valves when the fuel-air mixture hits the valve. It actually cools the valve slightly which causes the issue.

If the engine is “direct injection” the only place for carbon to build up is in the combustion chamfer itself. As Gene noted this is normally the result of lots of short trips in cold weather and not using a Top Tier gasoline.

If they already have the car partially disassembled and not drivable I’m not sure how she should proceed. Even if she has it flat-bedded to another shop this shop will expect to be paid for their work to this point. The next shop might want more than normal because as they will tell her “we have to correct the mess the other shop created.”

Thank you both for your replies. I have forwarded these to my sister. I was told that they removed the heads to inspect the cylinders which probably could have been done with a scope but I'm not 100% sure of that. If it was my car I would have them reassemble and use the solvent to clean up. Since the car has only 34,000 miles and was told that nothing else is wrong internally, I think that would be the most prudent and cost effective cure. After that I would be sure to get the engine up to 5000 rpm under a load regularly and be sure to use a top tier gasoline. Even Costco gas is top tier.
Thanks again!
Jeff

Direct injected engine will carbon the valves from the oil mist that comes through the PCV system. Engines that have the fuel injected in the intake manifold before the valves will help keep them clean.

Hi Denny,

I forgot about the PVC oil mist problem even on direct injection engines.

On my Audi they said that the problem with carbon build-up on the intake valves was due to the fuel in the fuel-air mixture condensing on them. It was aggravated by the VW-Audi CIS (continuous injection system) approach. Fuel was constantly being injected into the pre-combustion chamber head almost on top of the intake valve, even when it was closed.

Rusty I know some engines are more likely to have the problem. When I worked at the Saab dealer they used the CSI system and I don’t remember them having valve problems. Back in the 70’s lots of engines would build up enough carbon that would break loose and start knocking.