Usually a puff of black smoke upon start up is a sign of failed or failing valve stem seals.
Don
Don
Help with a piston soak problem aka did I destroy my engine?
- Thread starter jsean
- Start date
I did a B12 piston soak on my 3.6 VR6 and it handled it very well. Went from in excess 1qt/1k mi, to no measurable consumption in 8500 mi. I did run HPL oil first, and it cleaned a lot of crud out of the oil rings, but that didn't solve consumption.
It's been said a couple times, but wouldn't be surprised if your cats were saturated after the soak and significant oil consumption prior. Good luck
It's been said a couple times, but wouldn't be surprised if your cats were saturated after the soak and significant oil consumption prior. Good luck
Thanks for posting your experience! 8,500 miles with no consumption is impressive. Gives me a little more confidence that the piston soak will help with my VR6.I did a B12 piston soak on my 3.6 VR6 and it handled it very well. Went from in excess 1qt/1k mi, to no measurable consumption in 8500 mi. I did run HPL oil first, and it cleaned a lot of crud out of the oil rings, but that didn't solve consumption.
It's been said a couple times, but wouldn't be surprised if your cats were saturated after the soak and significant oil consumption prior. Good luck
What oil have you been running after the piston soak?
Interesting. I thought valve steam seals typically would be blue or blue grey puffs of smoke? And that black smoke is usually a sign of a leaky injector or something else causing the car to run rich?
HPL Euro 5W-30 came out after the piston soak, and HPL Euro 5W-30 went back in. Here's the full story:
2017 Porsche Cayenne w/3.6 VR6 - 81830 mi
At 4300 mi/half year into a run of HPL PCEO 5w30 Euro and completed a oil filter change yesterday. Like many others here it was catching crud, and I'm happy a new filter is in service.
Back story: Bought the Cayenne w/55k mi and it consumed oil at 1qt/4-5k mi - not a concern for me. However, after changing spark plugs at 74k mi, the consumption started to increase, and it used 1.5-2 qts in 3400 mi ahead of the change to HPL. Also, it began making a mess around the oil fill cap, presumably from blow by. Previous oil changes on my watch were a couple different flavors of liqui moly and redline, all good VW502 rated or recommended oils. Checked the PCV and it was working properly and not showing the typical symptoms of failure. My diagnosis was oil rings were gummed up. There is not a lot of info on it out there that I could find for the VR6, but it's common enough among VAG vehicles.
After changing to HPL it consumed 1qt in the first 1000mi. As hoped, the past 3000mi I've only had to add 1qt. Also, the oil fill cap is not an oily mess anymore. Exhaust tips are less sooty as well nowadays. Looking forward to further improvements.
Pictures:
A little grit in the filter cap:
View attachment 256337
Dirty housing - previously, it has been super clean when not using HPL:
View attachment 256338
Cleaned housing - please be forgiving of this cleaning job, the pictures don't illustrate how poorly accessible the housing is. I got what I could.:
View attachment 256339
filter did some work:
View attachment 256340
Filter is wrapped in paper towels and I'll cut it next weekend for a better look.
Thanks for sharing your experience and to those who replied to you. I have a 2017 Kia Sorento that started using 1.5 qts of oil every 1 k miles a year ago. or more. After 3 failed dealer piston soaks, I got a free new engine at 72,400. While this was going on I spent lots of time reading about piston soaks on YouTube and here. Happy to read that you got your vehicle running better. My son had a Passat that used lots of oil and I wish that I had known about the piston soaks then to help him save money. He got rid of it and don't know how much he lost on the deal.
Some places really cheat on repairs on these GDI cars.
Some places really cheat on repairs on these GDI cars.
Thanks for posting - I’m surprised the Kia dealership was willing to do piston soaks. Around here, dealerships and euro shops just flat out refused when I called and asked. Did they tell you what the failure mode on the engine was if their piston soaks didn’t help?
Out of curiosity, what year was your son’s Passat?
Wanted to update this thread - ended up doing an impromptu cross country road trip. About 4,300 miles. Total OCI ended up being 5,700 miles which is longer than what I intended it to be. Lots of keeping up with traffic driving during the trip. Lost about 4 notches on the dipstick - approx. 1/4th qt. Really happy with the piston soak results!
Going to send in a sample for the UOA.
Going to send in a sample for the UOA.
The question I have is where did all the B12 go during the piston soak? I think the OP said when he changed the oil after the piston soak it was not overfilled.
The OP should not have started the engine after the piston soak without changing the oil first.
The lesson to be learned is if you'd are buying a vehicle that will need a piston soak down the road, then you should buy a straight 4 or straight 6 engine.
The OP should not have started the engine after the piston soak without changing the oil first.
The lesson to be learned is if you'd are buying a vehicle that will need a piston soak down the road, then you should buy a straight 4 or straight 6 engine.
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I did verify oil level on the dipstick before I started it up post piston soak. My best guess is evaporation.
Chemtool claims that it’s fine to run the B12 in the crankcase for short periods before an oil change. I think I’m ok from that standpoint (but I only have shy of 6k miles, unsure how this will pan out long term).
V6s will be more challenging as you said, but it’s certainly doable if you tackle it as cylinder sets instead of the whole engine.
I think the biggest thing I wish I’d have known was that the exhaust system would get flooded. @KrisZ and @AdmiralYoda hit that nail on the head earlier in this thread.
He thinks 2006
So if the B12 was running through the rings as you hoped your oil sump would contain 12 cans of B12.
I don't care what the company says you never want to run the engine with any solvent in the crankcase. Probably no harm. But still.
I don't care what the company says you never want to run the engine with any solvent in the crankcase. Probably no harm. But still.
While it sounds like you mostly resolved your consumption issue it sounds like your VR6 might be a good candidate for Valvoline Restore and Protect. With how bad it was it sounds like it was pretty neglected before you got it.
You’re right and that’s what I got in there right now. I plan on running 3 more 5k OCIs with Valvoline Restore and Protect if the used oil analysis shows up as acceptable. After that I plan on switching to Mobil 1 Full Synthetic 0w40.
The carfax on this car shows regular oil changes between 6-7k miles at 2 shops. I called both shops and confirmed that they used the Castrol Edge 5w40.
My hypothesis is that both previous owners were octogenarians who used it to putz around town. Low RPMs with lots of around town driving imo contributed to the carbon buildup. That and an oil that meets VW502 but apparently doesn’t do a good job controlling carbon build up.
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Nice on the Valvoline, if it were me I would just keep the Valvoline going and not switch after a few oil changes. Baby that VR6 because that engine line is now dead and nothing will ever replicate the Chewbacca brrrrrr noise that the VR6 makes, going to be a very sad day when the last few of the Atlas and Passat VR6's are gone.
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