Audi SQ5 Smoke Points to Failed PCV System Fix

Had similar symptoms on my S4 2013 with the same engine family. The gray smoke during acceleration combined with power loss pointed directly to crankcase ventilation issues. The PCV system was completely clogged, causing excessive pressure in the crankcase and pushing oil through seals it shouldnt. The repair involved replacing the complete PCV valve assembly and cleaning the intake manifold. Oil was getting past the valve, contaminating the intake tract and causing the smoke at idle and during acceleration. The check engine light came on due to the system detecting incorrect crankcase pressure. This is a serious issue that needs prompt attention. If left unfixed, it can lead to oil consumption problems, damaged seals, and potential turbo issues. The repair took about 4 hours at the shop. The symptoms cleared up immediately after the fix. The failure of the PCV system is fairly common on these engines after 40-50k km. Regular oil changes with the correct spec oil help prevent premature failure. Would recommend getting it checked soon before it causes additional problems.

Thanks for sharing your experience with the PCV valve malfunction. My Audi had nearly identical symptoms, the smoke during acceleration was a clear sign something was wrong. My local mechanic found oil residue in the intake manifold during inspection, confirming the diagnosis. The PCV replacement fixed the idle issues and eliminated the smoke coming from the exhaust completely. Has your repair held up over time? Any maintenance requirements the shop mentioned to prevent future issues? Would be helpful to know the final cost of your repair too, since prices can vary quite a bit between shops. The leak diagnosis and labor costs were significant parts of my total bill.

The crankcase ventilation valve repair has held up perfectly since getting it fixed 2 years ago. No more smoke or engine performance issues. The total cost was 360 Euro which included labor and parts. It was worth every cent to prevent further damage to the engine. The mechanic recommended checking for oil leaks regularly and maintaining strict oil change intervals using only manufacturer-approved oil. They also suggested keeping the intake system clean to prevent future ventilation problems. The PCV system now works as intended with proper pressure regulation. Good preventive maintenance is key, I check under the car monthly for any signs of oil leaking and monitor oil consumption. The engine runs much smoother now without that gray smoke during acceleration. Having a properly functioning crankcase ventilation system really makes a difference in overall engine health. My advice is to stay on top of the regular maintenance schedule to avoid another valve failure. The repair cost is much better than dealing with major engine problems later.

I finally took it to my trusted mechanic last week after seeing your replies. The diagnosis matched exactly what you described, failed PCV valve causing excessive crankcase pressure. Total repair cost came to 420 Euro which included cleaning the intake manifold and replacing seals. The whole job took about 5 hours since they found some additional oil residue that needed cleaning. The smoke disappeared completely after the repair and the engine feels much stronger now. My mechanic showed me the old PCV valve which was completely gunked up with oil deposits. They recommended checking oil levels every 2 weeks and sticking to strict maintenance intervals to prevent future issues. The repair has completely fixed the emissions problem and eliminated the check engine light. Definitely glad I got it sorted before it caused more extensive damage. Makes sense now why the engine was feeling sluggish, that clogged PCV system was really affecting performance. No more leaks or pressure issues since the fix. This repair experience was actually quite positive compared to my previous mechanic visits.