VW Amarok Rough Idle & Poor MPG Points to Knock Sensor

Had the exact same poor performance issues on my 2015 VW Tiguan last month. The check engine light came on with similar symptoms, rough idle, increased fuel consumption, and hesitation during acceleration. After running diagnostics, it turned out the knock sensor wiring harness had significant corrosion at the connector. The sensor itself was fine, but the damaged wiring was causing incorrect ignition timing and throwing off the engine management system. The repair involved: Complete harness replacement, Cleaning connector terminals, Resetting engine management system, Test driving to confirm proper fuel efficiency This was a serious issue that required immediate attention since incorrect knock sensor readings can lead to engine damage if left unchecked. The faulty connection was causing the engine to run rich and retard timing unnecessarily. Would recommend getting it properly diagnosed with a scanner first. These symptoms could also indicate other issues like ignition coils or spark plugs, but the knock sensor connection problems are fairly common on this engine family. Proper diagnosis will save time and prevent replacing parts unnecessarily.

Thanks for sharing your experience with the knock sensor wiring issue. Those are almost exactly the same symptoms I experienced. Can you recall roughly how much you paid for the repair? My check engine light keeps flashing and the poor performance is really noticeable, especially during cold starts. Did you notice any other issues popping up after getting it fixed? The ignition timing problems you mentioned align with what I am experiencing. Getting quite concerned about potential engine damage, so want to make sure I budget appropriately for the repair work before taking it to a shop.

Just got my VW Amarok back from the mechanic last week. The initial diagnosis was spot on, it was indeed a faulty knock sensor connection causing all those performance issues and warning lights. Total repair cost came to 95€, which mainly covered fixing the cable connection to the sensor. The mechanic found corrosion in the wiring connector, similar to what I described before. Since the repair, the engine runs perfectly smooth again with normal fuel consumption. No more rough idling or ignition timing problems. The warning light disappeared immediately after they reset the system. Most importantly, catching this early prevented any serious engine damage. The quick fix means I avoided what could have been much costlier repairs down the line. No other issues have surfaced since the repair, the car performs just like it should. The relatively low repair cost was a relief, especially considering how significant the performance issues seemed. Getting proper auto repair diagnosis early really paid off in this case.

After reading advice here, I took my Amarok to an auto repair shop yesterday. The check engine light and rough performance had me worried, but the fix was straightforward and affordable. The mechanic confirmed what others mentioned, corroded wiring at the knock sensor connector was causing the issues. They completely replaced the wiring harness section and cleaned all connecting points. Total cost was 120€, which included diagnostic time and parts. Since the repair, the car runs perfectly again. Fuel efficiency is back to normal and the rough idling completely disappeared. The malfunction indicator light cleared right after they reset the system. No other car problems have shown up, and the engine feels much smoother during cold starts. Really glad I caught this early before it could cause more serious engine damage. Having that initial feedback here helped me better understand the issue and know what to expect at the shop. Definitely worth getting it properly diagnosed and fixed right away. Just wanted to close the loop and confirm it was indeed the knock sensor wiring causing all those symptoms. Thanks for the helpful guidance.