SQ8 Camshaft Sensor Failure Causing Power Loss

Had this exact problem with a 2017 S5. The symptoms match perfectly, hard starts and power loss were clear indicators of camshaft position sensor failure. The crankshaft and camshaft sensors work together to monitor engine timing, and when one fails, it causes noticeable performance issues. At the garage, the diagnostic revealed intermittent signal interruption from the camshaft sensor. In most cases, the issue stems from either a damaged sensor or faulty wiring connections. The repair involved replacing both the sensor and the associated wiring harness since corrosion had affected the connector pins. This is a serious issue that needs immediate attention, as continued driving with faulty timing signals can lead to engine damage. The camshaft sensor plays a crucial role in proper engine timing and fuel injection control. When it fails, the engine management system cannot accurately determine valve timing, leading to the misfires you mentioned. The repair was straightforward but required specialized diagnostic equipment to verify proper sensor operation after installation. Testing confirmed correct signal output and resolved all timing issues. Vehicle ran perfectly afterward with restored power and normal starting behavior.

Thanks for sharing your experience with the S5. This definitely sounds similar to what Im dealing with on my SQ8. The check engine light started appearing intermittently before the power loss became noticeable. Good point about the potential for engine damage, I will get it looked at this week. Can you recall roughly what you paid for the repair? Also, have you had any related issues since the sensor replacement? Im particularly concerned about whether this could be part of a larger camshaft position system problem.

Thanks for asking about the follow-up. After getting the SQ8 checked by my mechanic, the diagnosis confirmed your suspicions about the camshaft sensor. The issue was traced to a faulty cable connection rather than the sensor itself, which was fortunate as it meant a simpler fix. The repair cost came to 95 Euro for fixing the connection, which included testing to ensure proper signal transmission. This was much more reasonable than a complete sensor replacement would have been. Since the repair, the rough idling and timing issues have completely disappeared. The engine now runs smoothly with no power loss or starting problems. No related issues have occurred in the months following the fix, suggesting it was indeed an isolated problem with the wiring rather than a more complex camshaft position system issue. The mechanic checked the entire sensor circuit to ensure there were no other potential failure points. The crankshaft position sensor was also tested and showed normal readings, confirming the problem was limited to the camshaft sensor connection.

After all the helpful replies, I wanted to share how everything turned out. Took the SQ8 to a certified shop last week. They confirmed the camshaft sensor wiring was indeed the culprit, just like others experienced. The connector had significant corrosion causing intermittent signal issues. Total repair came to 280 Euro including diagnostic time and parts. They replaced the entire wiring harness section connected to the camshaft position sensor as a preventive measure. The crankshaft sensor checked out fine during testing. Car runs perfectly now, no more hard starts or power loss. The timing issues and misfires are completely gone. Really glad I addressed this quickly before it could cause any engine damage. The shop also performed a full system scan to ensure no other related issues were present.