Piston Soak made smoking way worse ?

[mops]

Hello.

TLDR; Piston soak procedure made smoking/oil consumption way worse. Car unusable now due to amount of smoke it creates. What now ?

Full story:

I have an Audi 3.0TFSI (petrol/gas) engine in a Q7 4L chassis (2012) - just under 80k miles on it. Apparently was a batch of them in 2012 with bad oil rings that would fail causing smoking and high oil consumption. I suspect I have the "lucky one".

It was taking oil... approx. 1L per 1000miles. Maybe a bit more. Also smoking slightly (white smoke), especially visible at idle - probably at speed not visible. Spark plugs showed excessive black deposits. Black exhaust tips. Foul smell when not moving. Situation somewhat improved after adding liquid molly stop smoke product.

It also had faulty PVC valve (no crankcase vacuum). I have read up and found that this could be contributing to oil consumption. I have also came across piston soak procedure that many people report have fixed or improved similar problems.

Over last two weeks I have 1. replaced pvc valve (crankcase vacuum now good in spec). 2. decarboned intake ports and swirl flaps (there were low to moderate amount of deposits there). 3. Performed the piston soak over the course of the week.

In my location Berryman B12 (recommended chemical for piston soak) is not available (I live in New Zealand, anything with toluene is banned here), so I used all sorts of different chemicals. Engine flush - strait into the cylinders for overnight soak, turning the engine by hand occasionally, then light degreasers, petrol injector cleaner, and finished by flushing cylinders with kerosene and finally with diesel to lubricate piston walls. Flushed the crankcase as best as I can with cheap oil and air and filled up fresh oil 5w-30.

The problem now is that is smokes WAY worse. All the time. idle, light loads smokes more and full load smokes ALOT (Think acrobatics plane with smoke trails, haha). Smoking only stops momentarily on overrun (ecu cuts fuel so no combustion)
Yes, install startup was like a locomotive, clouds of white smoke. But now when driving it smokes white/blue constantly. At idle/light loads white, but on full power rolling clouds of blue smoke - even at highway speeds. I have driven it just under 40 miles so far, but Im ashamed to take it on the road because of the clouds of smoke it leaves behind - people toot and point at me to let me know something is wrong with my car..... Over the 40 miles or so that I drove I did couple of redline pulls. Maybe the smoking is getting somewhat lesser (hard to say when its dark), but it is still way excessive.

Now, I know that fresh oil does not have stop smoke product in it. Im sure it would somewhat reduce the smoking but at this point the smoking is so bad that slight improvement will not make the car drivable. Other than that engine seems to be working fine. No misfires. No codes, good power. I am doing compression test later today but Im certain compression will be good because otherwise engine behaves well.

What are my options... other than replacing oil rings ? Which I will do if I have to but would rather not.

Im thinking of doing another piston soak with different chemicals. Perhaps turpentine, MEK cleaner, anything else ? During piston soak pressurize combustion chambers with compressed air to force fluid past the rings ? More Italian tuneup ? Heavier oil ?

 

[PontiacHO]

Is the air filter and/or intake clogged? That will cause the engine to “breathe” through the crankcase. If there’s sludge stopping up drain back holes, the oil could be puddling around the valves, drawing oil in the combustion chamber. Wondering also if the piston soak actually caused the oil rings to get stuck. Can you run a can of Seafoam in through a vacuum port to the point of flooding the engine out? Doing this when the engine is hot and then let it soak overnight. Your neighbors will think your crazy with all the smoke and engine revs but it’s definitely fixed stuck rings on many vehicles.

 

[Elkins45]

Is it possible that the mix of chemicals you used made things worse by just dislodging enough stuff to freeze the rings? If that’s the case I would definitely soak it again with something that’s a better solvent. Since toluene isn’t a possibility then maybe MEK and acetone if you can get it.

Is toluene banned for everything? Can you get it at a paint or hardware store?

 

[twX]

Did you test drive the vehicle after the PCV replacement but before the piston soak? If not, I wouldn't just assume that the piston soak is to blame.

White smoke is often from coolant, and blue smoke oil. It sounds like these engines have both oil and coolant running through the PCV assembly. Did any oil and coolant spill during the PCV replacement? Are you sure the oil and coolant connections are properly gasketed? Are you losing coolant?

 

[spasm3]

The solvents removed the oil from the cylinder walls . I'm not sure diesel fuel had enough lubricity. Xx-30 oil would have been good. You might have created more wear.

 

[mops]

Is it possible that the mix of chemicals you used made things worse by just dislodging enough stuff to freeze the rings? If that’s the case I would definitely soak it again with something that’s a better solvent. Since toluene isn’t a possibility then maybe MEK and acetone if you can get it.

Is toluene banned for everything? Can you get it at a paint or hardware store?

Yes, thats the plan. I have MEK. Toulene just not available at all anywhere.

 

[mops]

Did you test drive the vehicle after the PCV replacement but before the piston soak? If not, I wouldn't just assume that the piston soak is to blame.

White smoke is often from coolant, and blue smoke oil. It sounds like these engines have both oil and coolant running through the PCV assembly. Did any oil and coolant spill during the PCV replacement? Are you sure the oil and coolant connections are properly gasketed? Are you losing coolant?

No, I have not test drove between. Because of how the engine is built, PVC replacement is a big job, so all was done as one. You are right these have coolant running through PVC assembly. yes there were spillages during work but cylinders, crankcase and intake tract was subsequently flushed and cleaned up.

There is no noticeable loss of coolant. Having said that there's no noticable loss of oil either. But this engine takes 7L of oil so large volume and its hard to say from the dipstick, which is only about 5mm from low to high state.

 

[mops]

Update. Have done cold compression test. all cylinders between 11 and 12 bar, which I would say is ok. The one with 11 bar has a slight leak in valve - I have noticed this while de-carboning. no change after adding some oil and re-doing the test.

Also pics of plugs before and after the operation. Pic with 6 plugs is before. pics with 3 plugs is after.

I see heavy white deposits on cylinders 1, 3 and 5. The other seem to be looking ok-ish ?

Some say white deposits is burning coolant. Some say it can be oil ash. Smoke at idle is white, but with load is progressively more blue (definitely blue at full load).

Seafoam is not popular in this country. I'll see if I can find it. The plan for tonight is italian tuneup. Failing that I'll do a second soak.

 

[Opelman]

You possibly loaded the exhaust system with your cleaning solutions. It might take a while to get the exhaust and muffler hot enough to burn it all out.

 

[Trav]

^This, it can take some time/miles to rid the system on the chemicals and yes it will smoke like an old steam engine.

 

[AdmiralYoda]

You have a V6, not an inline-4. Any "V" engine is going to be problematic because the B12 will only sit on one side of the cylinder unless you put a ton of it in there to fully submerge the piston/rings.

Thoughts:

1. Only one half of the rings got clean so that may create some weird oil sealing issues.
2. You rotated the engine with a bunch of chemicals in there. Worst case is that you can hurt the motor as liquid doesn't compress. Best case you were sending all these fluids into the exhaust system when the piston was at TDC.

I'm guessing you have a ton of oil, B12, kerosene, and junk in your exhaust that is burning off.

More importantly, how is your oil consumption? What weight of oil are you using and what does the owners manual call for? It might be worth going to a heavier grade of oil and using product like HPL's EC30 or Valvoline Restore and Protect to help clean the rings.

Take it out for a very long drive on country road at night when there are few people around to dry and get all the junk out of the exhaust. Don't beat on it but keep the RPM's up a bit.

Another option is BG's EPR-109 engine flush which is known to help clean rings.

 

[RMaybeth]

1. Only one half of the rings got clean so that may create some weird oil sealing issues.
2. You rotated the engine with a bunch of chemicals in there. Worst case is that you can hurt the motor as liquid doesn't compress. Best case you were sending all these fluids into the exhaust system when the piston was at TDC.

I'm thinking he probably only rotated the engine with the spark plugs out?

And, I'm on board w everybody else saying the inside of the exhaust system is probably loaded up with chemicals that make all the smoke. And the reason smoke is still coming out after 40 miles is because there's a lot of solvent still left inside the exhaust, especially the cooler sections that are nearer the tail-pipe and that won't burn off as fast.

 

[Donald]

Maybe you had crud deposits around the oil control rings that helped them seal better. The crud was removed with your piston soak and now the oil control rings are sealing worse than they were with the crud.

Time will tell. New rings may be the only fix.

 

[burbguy82]

i did a b12 soak, and it blew a bunch of nasties in the oil.

 

[mops]

To answer common questions
1. of course when I rotated engine by hand the plugs and injectors were out.
2. of course some chemical got into the exhaust. in fact so much the I saw some leaking around exhaust mid-point where exhaust sections are joined. Never the less I would expect these to burn off in about a total of 1 hr of driving so far.

Update:

I managed to organize a boroscope and it turns out there are much bigger problems there then poor sealing rings.
-All 3 cylinders in the left bank have cylinder wall scoring. Im not an expert on the subject but I think this looks major. I cannot believe that compression test is showing good compression on those cylinders ? Also, whats odd is that all the damage is on the top part of the cylinder wall. I was expecting to see damage on the bottom, as in was expecting debris to collect in the lowest point and get jammed between piston and wall and cause scoring, but thats not the case.
-the cylinder scoring in all cases starts about 1/4 way down the bore and is more sever at the bottom then the top. Does that point to some known cause ? Maybe leaking injectors washing this area of the bore ?
-in the failed cylinders there are significant deposits on the exhaust valves. some look like they chipped off.
-All cylinders on the right bank look fine with maybe some minor lines. In fact its amazing how clean the pistons are after the soak.
-even the good cylinders are showing dark oily deposits on the cylinder head and valves. how would that be ? maybe oily blowy is being recirculated into the intake... but then again i have just put in brand new PVC valve



I dunno whats next. I called around local part places and none have replacement engines on hand.
Given its an alloy block, its repairable by inserting iron sleeves - but of course it is not cheap.
Im also thinking getting a bottle of this ring seal chemical - I have used it in the past in another car with great success, Im sure it will reduce smoking, but I doubt it will fix the issue to the point where car is usable.

These issues are commonly reported on Audi forums for this particular engine. There exist an "evo" version of this engine block with factory installed steel sleeves, which is not subject to those issues, but the alloy ones specifically installed in Q7 are common.

[EDIT] Ignore the date on the pics - its wrong. Pics taken yesterday.

 

[svtrit]

How attached to this car are you? I’d be shopping for a new one. That engine is shot.

Thanks for sharing your story.

 

[ElectroMechanoMan]

Unless the sleeve job you mentioned can be done in frame, like a farm tractor or otr diesel, I’m sorry, I have to agree with svtritt. If these engines were known to have ring trouble, my guess is a cracked ring or overheating.

 

[Oliveoil2]

Ouch!! Thanks for the update. Looks like this engine ran hot for a period of time.

 

[sw99]

At least you found out what is going on in there.

 

[Exhaustgases]

I'd say these piston soaks are as detrimental as a power flush of a high mile automatic transmission.
That carbon and goo may be the glue that keeps things sealed for the time being.