Oil in Spark Plug Tube. New Cylinder Heads? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

GrandAmGT · 07-24-2024, 09:22 AM

Hello, Camaro family. I have a 2010 with the V6 LLT engine, and it has 98,600 miles on it. A few weeks ago the car started misfiring while I was driving, it was idling rough and was hard to start. My code scanner detected DTC P0300.

I took the car to a Chevrolet dealership and they said that there was oil in the spark plug tubes and on the spark plugs that was causing the misfires. The dealership said that I need to replace the cylinder heads at a cost of $8,000. They further said that there was a manufacturing problem with the heads that caused them to become porous, thus allowing oil to seep into the spark plug tubes. I found this TSB that describes the issue across a wide range of GM vehicles: https://static.nhtsa.gov/odi/tsbs/20...29900-9999.pdf

Has anyone encountered this problem? Is replacing the cylinder head really the only permanent fix? Thank you.

gtstorey · 07-24-2024, 09:49 AM

I guess it depends on if they eliminated the seals as the leak point.

And how long does it take to build up oil enough to cause a problem. For $8k, you could clean it out and swap plugs a lot of times.

And $8k seem like a lot for replacing heads if needed. Looks like parts are about $2k.

Find a good independent shop to take it to.

GrandAmGT · 07-24-2024, 10:34 AM

Quote:

Originally Posted by gtstorey

I guess it depends on if they eliminated the seals as the leak point.

And how long does it take to build up oil enough to cause a problem. For $8k, you could clean it out and swap plugs a lot of times.

And $8k seem like a lot for replacing heads if needed. Looks like parts are about $2k.

Find a good independent shop to take it to.

Thank you for your advice. The dealership service tech did offer to simply clean the spark plugs and tubes to get the car running again, but he said this was a temporary fix. I was thinking that the problem was not occurring over 98,000 miles, but that it started happening recently due to the age of my car. That's the question: How fast is the oil seeping in? If it was happening over 98,000 miles then I'm good to go with just a cleaning. But if it started happening over the last 1000 miles, then that's really bad. Regardless, I'm going to see an independent shop for a second opinion.

morepowerjoe · 07-24-2024, 10:35 AM

I agree with gtstorey. I would find a good a good independent shop and get
them to give you a diagnosis and a quote and not tell them what the dealer told you and see what they say.

gtstorey · 07-24-2024, 10:51 AM

Quote:

Originally Posted by GrandAmGT

Thank you for your advice. The dealership service tech did offer to simply clean the spark plugs and tubes to get the car running again, but he said this was a temporary fix. I was thinking that the problem was not occurring over 98,000 miles, but that it started happening recently due to the age of my car. That's the question: How fast is the oil seeping in? If it was happening over 98,000 miles then I'm good to go with just a cleaning. But if it started happening over the last 1000 miles, then that's really bad. Regardless, I'm going to see an independent shop for a second opinion.

No way of knowing how long it will take to start causing a problem but it's probably somewhere between 1000 and 98,000 miles. Only way to know is to clean it up and see how long it takes to become a problem.

DirtyDirt · 07-24-2024, 11:18 AM

i agree with morepowerjoe on taking it to an independent shop and getting their diagnosis and quote, without telling them what the "Stealer" said... lol, they call them 'Stealerships" for a reason

PaulsSS · 07-24-2024, 05:41 PM

just went through this on a Saturn. Few of the spark plug holes had filled up with oil. Of course would never fix such a obvious poor engineering problem. We cleaned the holes out with paper towels and alcohol new plugs and so far no more trouble. I recommend switching to high mileage engine oil. May help some as its thicker. You don't know till you clean every thing up how long it will take to fill up with oil again. May take another 100k?

InFiD3ViL · 07-24-2024, 09:32 PM

Sweet Jesus! $8000? You could buy a another used good condition V6 5th gen for that cost. That's actually fairly close to a decent condition high milage SS. Not quite, but close.

GrandAmGT · 07-25-2024, 08:33 AM

Quote:

Originally Posted by InFiD3ViL

Sweet Jesus! $8000? You could buy a another used good condition V6 5th gen for that cost. That's actually fairly close to a decent condition high milage SS. Not quite, but close.

Exactly. I can put that money towards buying another car, and I just may do that if I can't get a more satisfying answer from another shop. The labor quote, alone, was $4000.

gtstorey · 07-25-2024, 08:41 AM

I looked up the cost of the heads on a GM parts website and they were something like $900 each. That isn't everything but I don't think the additional stuff would be anything like an additional $2k+. I would think $4K would be more than a fair total cost.

ariZona28 · 07-25-2024, 09:46 AM

I know what I'll do if my little V6 develops this problem. Hit 'em with the "Rag Wrench", maybe a little brake cleaner, compressed air, a little electrical contact cleaner for the coil/boot assembly then reassemble and send it! I'd do an inspection after a month or so to see how much oil comes back. No way I'm swapping heads at $2 to $8K. Our cars are getting up there in age and sometimes you need to apply some mechanical work arounds for continued service.

AlisoBob · 07-25-2024, 11:12 AM

Buy new tubes, swap them out..... done.

acutron42 · 07-25-2024, 12:38 PM

Quote:

Originally Posted by AlisoBob

Buy new tubes, swap them out..... done.

I am not to familiar with these engines, but aren't there seals also? I would check the torque on the bolts too.

GrandAmGT · 07-25-2024, 02:33 PM

Quote:

Originally Posted by AlisoBob

Buy new tubes, swap them out..... done.

According to the technical service bulletin I posted the link to, the tubes are integrated into the cylinder heads and are not removable.

07-24-2024, 09:22 AM	#1
GrandAmGT Drives: 2010 1LT & 2016 Cadillac CTS V6 Join Date: Apr 2015 Location: Danville, Virginia Posts: 376	Oil in Spark Plug Tube. New Cylinder Heads? Hello, Camaro family. I have a 2010 with the V6 LLT engine, and it has 98,600 miles on it. A few weeks ago the car started misfiring while I was driving, it was idling rough and was hard to start. My code scanner detected DTC P0300. I took the car to a Chevrolet dealership and they said that there was oil in the spark plug tubes and on the spark plugs that was causing the misfires. The dealership said that I need to replace the cylinder heads at a cost of $8,000. They further said that there was a manufacturing problem with the heads that caused them to become porous, thus allowing oil to seep into the spark plug tubes. I found this TSB that describes the issue across a wide range of GM vehicles: https://static.nhtsa.gov/odi/tsbs/20...29900-9999.pdf Has anyone encountered this problem? Is replacing the cylinder head really the only permanent fix? Thank you.

07-24-2024, 10:35 AM	#4
morepowerjoe Drives: 2012 Chevrolet Camaro l99 Join Date: Aug 2020 Location: Austin, TX Posts: 2,232	I agree with gtstorey. I would find a good a good independent shop and get them to give you a diagnosis and a quote and not tell them what the dealer told you and see what they say. __________________ DSS Pistons, Eagle ESP L19 Rods, ARP Head and Main Studs, TSP PRC CNC Ported Heads milled .030, Cometic .040 Head Gaskets, GPI SS3 VVT Camshaft, GM Racing Lifters, CHE Trunnions, Melling 10355HV Oil Pump, Cold Air Inductions CAI, Fast LSXR Intake Manifold, Nick Williams 103 TB, TSP Longtubes, ZL1 Fuel Pump, Mishimoto Radiator and Oil Cooler, 3600 Circle D Converter, Tru Cool 40k Tranny Cooler, Fluid Dynamics Balancer, EBC 3GD Rotors with EBC Bluestuff NDX Pads, Bilstein B6 Shocks / Struts with Eibach ZL1 Drop Springs Build Thread https://www.camaro5.com/forums/showthread.php?t=609817

07-24-2024, 11:18 AM	#6
DirtyDirt Drives: 2013 Camaro ZL1 Join Date: Jun 2022 Location: Michigan Posts: 594 View My Garage	i agree with morepowerjoe on taking it to an independent shop and getting their diagnosis and quote, without telling them what the "Stealer" said... lol, they call them 'Stealerships" for a reason __________________ 2010 2SS SOLD 10-28-23 2013 ZL1 BOUGHT 10-29-23 With 1950 miles K&N Full CAI 15% tint Borla ATAK Cat Back Exhaust Pedal Commander Headers and Tune

07-24-2024, 09:32 PM	#8
InFiD3ViL Drives: 2010 CGM 2SS/RS LS3 Swapped A6 Join Date: Sep 2016 Location: Spring Hill, FL Posts: 4,737	Sweet Jesus! $8000? You could buy a another used good condition V6 5th gen for that cost. That's actually fairly close to a decent condition high milage SS. Not quite, but close. __________________ 2010 CGM Camaro 2SS LS3 Swapped A6 - GPI LS3 SS1 .647/.638, (224/237, 112 +4, 7º overlap) on CamMotion 8620 core, BTR Platinum .660" Dual Spring kit w/titanium retainers, CHE bronze trunnion upgrade, stock heads milled @ .015, Melling HV 10296 oil pump, TSP 1-7/8" long tube headers (W/Catless Off-road Pipes), Corsa Xtreme 3" Catback, GPI Ported/Rod Mod Intake, Stage 2 Ported Throttle Body, Vararam OTR CAI, Mike Norris Gen 2 catch can + GM 1LE clean side separator, 160º thermostat - Megan Racing adjustable coilovers (lowered 1.75"), MRR M017 10/11" wheels-Tuned by Ryan @ GPI

07-25-2024, 09:46 AM	#11
ariZona28 Give speed a chance Drives: 2015 Camaro 2LS, 2015 Camaro Z/28 Join Date: Nov 2019 Location: Mesa, Az Posts: 2,797	I know what I'll do if my little V6 develops this problem. Hit 'em with the "Rag Wrench", maybe a little brake cleaner, compressed air, a little electrical contact cleaner for the coil/boot assembly then reassemble and send it! I'd do an inspection after a month or so to see how much oil comes back. No way I'm swapping heads at $2 to $8K. Our cars are getting up there in age and sometimes you need to apply some mechanical work arounds for continued service. __________________ 2LS: a TREMENDOUS machine. Z/28: it's a BIT MORE POWERFUL, of course.

07-24-2024, 09:49 AM	#2
gtstorey Drives: 2010 Camaro SS2,L99, LSA SC Join Date: Aug 2017 Location: Huntsville, AL Posts: 2,450	I guess it depends on if they eliminated the seals as the leak point. And how long does it take to build up oil enough to cause a problem. For $8k, you could clean it out and swap plugs a lot of times. And $8k seem like a lot for replacing heads if needed. Looks like parts are about $2k. Find a good independent shop to take it to.

07-24-2024, 05:41 PM	#7
PaulsSS Account Suspended Drives: 15SS Camaro Join Date: Dec 2020 Location: US Posts: 351	just went through this on a Saturn. Few of the spark plug holes had filled up with oil. Of course would never fix such a obvious poor engineering problem. We cleaned the holes out with paper towels and alcohol new plugs and so far no more trouble. I recommend switching to high mileage engine oil. May help some as its thicker. You don't know till you clean every thing up how long it will take to fill up with oil again. May take another 100k?

07-25-2024, 08:41 AM	#10
gtstorey Drives: 2010 Camaro SS2,L99, LSA SC Join Date: Aug 2017 Location: Huntsville, AL Posts: 2,450	I looked up the cost of the heads on a GM parts website and they were something like $900 each. That isn't everything but I don't think the additional stuff would be anything like an additional $2k+. I would think $4K would be more than a fair total cost.

07-25-2024, 11:12 AM	#12
AlisoBob Drives: Camaro 2SS Gen 5 Join Date: Oct 2023 Location: Orange County Ca Posts: 169	Buy new tubes, swap them out..... done. Attached Images